a dad pushes tangentially on a small hand-driven merry-go-round and is able to accelerate it from rest to a frequency of 15 rpm in 10.0 s. assume the merry-go-round is a uniform disk of radius 2.5 m and has a mass of 330 kg, and two children (each with a mass of 25 kg) sit opposite each other on the edge. calculate the torque required to produce the acceleration, neglecting frictional torque. what force is required at the edge?

Answer:

Here is answer

Explanation:

a) The weight of the solid 'S' is a contact force because it acts on the solid 'S' through physical contact with the ground.

b) The characteristics of the weight of solid 'S' are:

It acts in the downward direction.

It is a gravitational force that is exerted by the Earth on the solid 'S'.

It is equal to the mass of the solid 'S' multiplied by the acceleration due to gravity (W = m*g).

c) The weight of solid 'S' can be represented by a vector as shown below:

[asy]

unitsize(1cm);

draw((0,0)--(0,15),Arrow(6));

label("$W$", (0,7.5), W);

[/asy]

a) The other forces acting on solid 'S' are the normal force exerted by the inclined plane on the solid 'S' and the frictional force exerted by the inclined plane on the solid 'S'. The normal force is a contact force, while the frictional force is also a contact force.

b) These forces can be represented by vectors as shown below:

[asy]

unitsize(1cm);

draw((0,0)--(0,15),Arrow(6));

label("$W$", (0,7.5), W);

draw((0,0)--(15sqrt(2)/2,15/2),Arrow(6));

label("$N$", (7.5sqrt(2),7.5), NE);

draw((0,0)--(-15sqrt(2)/2,-15/2),Arrow(6));

label("$F_f$", (-7.5sqrt(2),-7.5), SW);

[/asy]

c) The characteristics of these forces are:

The normal force acts perpendicular to the surface of the inclined plane.

The frictional force acts in the opposite direction to the direction of motion or intended motion of the solid 'S'.

The magnitude of the normal force is equal to the weight of the solid 'S', but in the opposite direction.

The magnitude of the frictional force depends on the coefficient of friction between the solid 'S' and the inclined plane, as well as the normal force.

a) The new force acting on solid 'S' is the gravitational force, which is a force acting from a distance.

b) The characteristics of the gravitational force are:

It acts in the downward direction.

It is a force that is exerted by the Earth on the solid 'S'.

Its magnitude can be represented by the vector shown below (using a scale of 1 cm to represent 1.3 N):

[asy]

unitsize(1cm);

draw((0,0)--(0,-1.3),Arrow(6));

label("$W$", (0,-0.65), S);

[/asy]

Let us find first the forces at 1, 2 & 3 points.

We know that ke= 8.99 * 109N.m2 / C2

The forces are: -

F1 = keq1q2 / r212 = {8.99 * 109N.m2 / C2} * {10 * 10-6 C} * {40 * 10-6 C} / {10 * 10-2 m}2

F1 = 359.6 N

F2 =keq1q3 / r213 = {8.99 * 109N.m2 / C2} * {10 * 10-6 C} * {30 * 10-6 C} / {30 * 10-2 m}2

F2 = 29.96 N

F3 = keq2q3 / r213 = {8.99 * 109N.m2 / C2} * {40 * 10-6 C} * {30 * 10-6 C} / {20 * 10-2 m}2

F3 = 269.7 N

Now,

The net force on q1 is F1 – F2,

i.e. F1 + F2 = 359.6 + 29.96

F(q1) = 389.56 N to the left

To learn more about Coulomb’s Law:

https://brainly.com/question/66110

#SPJ1

The required values are a) T = 2.3 seconds, b)  f = 0.434 Hz, c) ω = 2.7 rd/s.

Simple harmonic motion, a particular kind of periodic motion in which a particle repeatedly oscillates around a mean location, In U-tube oscillating liquid column motion is hence simple harmonic.

Given,

Time = 11.5 seconds to five complete vibrations.

a) Time period is time taken to complete one vibration,

So T = 11.5/5 = 2.3 seconds

b) Frequency(f) = 1/T

f = 1/2.3 = 0.434 second inverse.

c) By using formula of angular frequency ω = 2π/T

ω = 2π/2.3 = 2.7 hz

Thus, final values are a) T = 2.3 seconds, b)  f = 0.434 second inverse, c) ω = 2.7 rd/s.

To know more about simple harmonic motion visit:

brainly.com/question/28208332

#SPJ4

(a) The normal force is 267.7 N and frictional force is 980 N.

(b) The minimum coefficient of static friction is 0.27, which is needed to prevent slipping at the base.

(c) The direction of the contact force is 1016 N.

∈(t) = 0

N₂ ( L sinθ ) = 800 ( [tex]\frac{L}{3}[/tex] cosθ )

N₂ = 267.7 N

(a) Normal force F(d) = N₂ = 267.7 N

Frictional force N = 800 + 180

                         N = 980 N

(b) The minimum coefficient of static friction,

F(d) = μ N₁

μ = F / N₁

μ = 267.7 / 980

μ = 0.27

(c) The direction of the contact force,

R = [tex]\sqrt{(980)^{2} + (267.7)^{2} }[/tex]

R = 1016 N

To learn more about Coefficient of static friction, Here :

https://brainly.com/question/24173409?referrer=searchResults

#SPJ4

Answer:

Below

Explanation:

Normal force will be   mg cos 15° = 1.5*9.81 cos 15°   Newtons

Downplane force will be  mg sin 15° = 1.5 * 9.81  sin 15°    N

Acceleration

F = ma

F/m = a

1.5 ( 9.81) sin 15° / 1.5   m/s^2  = a

Answer: Hookes law states F=kX where F is the force applied, k is the spring constant, and X is the extension of the spring from its resting point.Substituting the values in, we get:F=100*(0.65-0.5)=100*0.15=15N

The time period of the small oscillations for the simple pendulum is found to be  3.14 seconds.

The pendulum is located in an elevator that is accelerating upwards with an acceleration of 6m/s² and length of the pendulum is 4m.

Because the elevator is accelerating in the upper direction the net acceleration of the pendulum will be (10 + 6)m/s².

The period of small accelerations for this pendulum will be given by the relation,

T = 2π(l/a)

Where,  l is the length of pendulum and a is the net acceleration.

Putting values,

T = 2π(4/16)

T = 2π(1/2)

T = π seconds.

T = 3.14 seconds.

So, the time period of this small oscillations for this pendulum is 3.14 second.

To know more about oscillations, visit,

https://brainly.com/question/12622728

#SPJ4

If the cart moves in 3.2 seconds from rest, then the distance traveled by cart is 2 meters.

How do you define distance? Regardless of direction, distance measures an object's overall movement. Distance is defined as the amount of ground covered by an object, regardless of its starting or stopping position.

Horizontal force acting on the cart, F = 11 N

Mass of the cart, m = 35 kg

To find,

Distance covered by the cart in 3.5 seconds if it starts from rest.

Solution,

Let x is the distance moved by the cart. It can be calculated using the second equation of motion as :

s = 1.925 meters

In terms of "how much land an object is covered" while traveling, distance—a scalar quantity—describes this. Displacement is a vector number that expresses the overall change in the object's location, and it is related to the phrase "how far from place the thing is."

To know more about distance  visit:

https://brainly.com/question/15172156

#SPJ4

4.71 s long (in s) does it take a child on a swing to complete one swing if her center of gravity is 5.53 m below the pivot.

The average position of an object's weight is known as its center of gravity. Any object's travel through space may be entirely explained in terms of how its gravitational center moves from one location to another and, if it is free to spin, how it rotates around that center of gravity. Calculations combining gravitation and dynamics may be made much simpler by treating an object's mass as though it were concentrated at a single location.

T=2π√(l/g)

T=2π√(5.53/9.81)

T=4.71

T =4.71 s

To know more about center of gravity visit:

https://brainly.com/question/20662235

#SPJ4

The volume of the toy is 80 ml.

To find the volume of the plastic toy, Maher can use the principle of buoyancy. When an object is placed in a fluid, it will displace an amount of fluid equal to its own volume. The volume of the displaced fluid can be measured and used to calculate the volume of the object.

In this case, Maher has placed the toy in a graduated cylinder filled with water, and he has observed that the water level increased from 70 ml to 150 ml. This means that the toy displaced 150 - 70 = 80 ml of water.

The volume of the toy is equal to the volume of the displaced water, so the toy's volume is 80 ml. This is the volume of the toy when it is completely submerged in water.

It's important to note that the volume of an object can change depending on its temperature, pressure, and other factors. To get an accurate measurement of the volume of the toy, Maher should make sure to measure the volume of the displaced water carefully and under controlled conditions.

Answer:

Volume of the toy: [tex]80\; {\rm mL}[/tex].

Average density of the toy: [tex]2\; {\rm g\cdot mL^{-1}}[/tex] (or equivalently, [tex]2\; {\rm g \cdot cm^{-3}}[/tex].)

Explanation:

The graduated cylinder initially measures the volume of water in this cylinder:

[tex]V(\text{water}) = 70\; {\rm mL}[/tex].

Assume that the toy is submerged in the water. The graduated cylinder would then measure the volume of the water and the toy, combined:

[tex]V(\text{water}) + V(\text{toy}) = 150\; {\rm mL}[/tex].

Rearrange to find the volume of the toy:

[tex]\begin{aligned}V(\text{toy}) &= 150\; {\rm mL} - V(\text{water}) \\ &= 150\; {\rm mL} - 70\; {\rm mL} \\ &= 80\; {\rm mL}\end{aligned}[/tex].

To find the average density of this toy, divide mass by volume:

[tex]\begin{aligned}(\text{average density}) &= \frac{(\text{mass})}{(\text{volume})} \\ &= \frac{160\; {\rm g}}{80\; {\rm mL}} \\ &= 2\; {\rm g\cdot mL^{-1}}\end{aligned}[/tex].

The relation between the time-period of the transverse wave for the third harmonic and the time between the maximum displacement and minimum displacement is [tex]=16.3 \mathrm{~g}[/tex]

[tex]$$T_3=2 t$$Substitute$8.40 \mathrm{~ms}$[/tex]

for t in the above expression.

[tex]$$T_3=2(8.4 \mathrm{~ms})\left(\frac{10^{-3} \mathrm{~s}}{1 \mathrm{~ms}}\right)$$[/tex]

The wave velocity can be given by the following expression [tex]=0.0168 \mathrm{~s}[/tex]

[tex]v=\frac{\lambda_3}{T_3}[/tex]

Here,

[tex]$$\lambda_3$$[/tex]

is the frequency of third harmonics and

[tex]$$T_3$$[/tex]

is the time-period of third harmonics.

Substitute [tex]$0.1296 \mathrm{~m}$[/tex] for

[tex]$$\lambda_3$$[/tex]

and

[tex]$0.0168 \mathrm{~s}$ for$T_3$[/tex]

[tex]\begin{aligned}& v=\frac{0.1296 \mathrm{~m}}{0.0168 \mathrm{~m}} \\& =7.714 \mathrm{~m} / \mathrm{s}\end{aligned}[/tex]

The expression of the wave velocity is given by the following expression.

[tex]v=\sqrt{\frac{T}{m / L}}[/tex]

Rearrange the above expression for

[tex]$$m$$[/tex]

[tex]\text { Substitute } 5.00 \mathrm{~N} \text { for } T, 0.1944 \mathrm{~m} \text { for } L \text {, and } 7.714 \mathrm{~m} / \mathrm{s} \text { for } v \text { in the above expression. }[/tex]

[tex]\begin{gathered}m=\frac{(5.00 \mathrm{~N})(0.1944 \mathrm{~m})}{(7.714 \mathrm{~m} / \mathrm{s})^2} \\=(0.0163345 \mathrm{~kg})\left(\frac{1000 \mathrm{~g}}{1 \mathrm{~kg}}\right) \\=16.3 \mathrm{~g}\end{gathered}[/tex]

The anti-nodes in the standing waves are at a distance half a wavelength. The time-period is twice the time from maximum displacement to minimum displacement of the anti-node.

To learn more about displacement visit

https://brainly.com/question/11934397

#SPJ4

Answer:

To make a simple model of the solar system that can be used to compare the time it would take for a spaceship to travel between different planets, the student must accurately represent the relative distances between the planets. This is because the time it would take for a spaceship to travel between two planets depends on the distance between those planets, so accurately representing the distances between the planets is essential for thinking about how long it would take for a spaceship to travel between them.

It is not necessary for the student to make sure that the model of each planet looks like the planet it represents, although this may help make the model more understandable. The most important thing is that the model accurately represents the relative distances between the planets.

In summary, the student must accurately represent the relative distances between the planets in order to think about how long it would take for a spaceship to travel between different planets in the solar system.

Relative to the observer in on the shore, the velocity of the boat is 6.5 m/s, NE.

What is relative velocity?

The velocity of an object in relation to another observer is known as its relative velocity.

We cay say that the relative velocity is equal to the vector difference between the velocities of two objects. The relative velocity of A with respect to B= velocity of the body A – velocity of the body B.

The diagram below shows the calculation where AC is relative speed, AB is speed of the boat and BC is the speed of stream.

To learn more about relative velocity from the given link

https://brainly.com/question/19260269

#SPJ1

The second weight of mass 96 g must be located at the 9 cm mark on the meter stick to keep it balanced.

To determine the location of the second weight that will keep the meter stick balanced, we need to consider the principles of equilibrium.

The weight of the meter stick can be calculated as follows:

Weight of meter stick = mass * acceleration due to gravity

= 24 g * 9.8 m/s^2

= 235.2 N

The total weight of the two hanging weights is 96 g + 96 g = 192 g = 1.92 N.

The sum of the forces acting on the meter stick is equal to zero when:

235.2 N + 1.92 N = 0

This equation tells us that the sum of the forces acting on the meter stick is equal to zero when the total weight of the two hanging weights is equal to the weight of the meter stick.

To determine the location of the second weight, we also need to consider the moments about the pivot point. The moment of a force is calculated as the product of the force and the distance from the pivot point. The moments about the pivot point are equal to zero when the sum of the moments of the forces on one side of the pivot point is equal to the sum of the moments of the forces on the other side of the pivot point.

The moment of the weight of the meter stick about the pivot point is calculated as follows:

Moment of the weight of meter stick = force * distance from pivot point

= 235.2 N * 0.4 m

= 94.08 N*m

The moment of the weight hanging from the 9 cm mark about the pivot point is calculated as follows:

Moment of weight hanging from 9 cm mark = force * distance from pivot point

= 1.92 N * 0.09 m

= 0.1728 N*m

To keep the meter stick balanced, the moment of the second weight must be equal in magnitude but opposite in direction to the moment of the weight hanging from the 9 cm mark. The moment of the second weight can be calculated as follows:

Moment of second weight = force * distance from pivot point

= 1.92 N * distance from pivot point

Substituting the value of the force and setting the moment equal to the negative of the moment of the weight hanging from the 9 cm mark, we get the following equation:

1.92 N * distance from pivot point = -0.1728 N*m

Solving for the distance from the pivot point, we find that the second weight must be located at a distance of 0.09 m from the pivot point, or 9 cm. This is the same distance from the pivot point as the weight hanging from the 9 cm mark.

Therefore, the second weight of mass 96 g must be located at the 9 cm mark on the meter stick to keep it balanced.

Learn more about Mass here:

https://brainly.com/question/19385703

#SPJ4

We may be aware that, for example, a car leaving a stop sign would move farther in a given amount of time the faster it accelerates.

acceleration is the rate of change in both speed of velocity over time. When anything moves faster or slower in a straight line, it is said to have been accelerated. So because direction is always shifting, motion on a circle accelerates even while the speed is constant.

An object's velocity is altered by a net force, and acceleration increases with net force. To accelerate at the same rate as less massive objects, more massive objects need greater net forces.

To know more about acceleration visit:

https://brainly.com/question/2303856

#SPJ1

So let's talk about billiard balls and the law of conservation of momentum. For the purposes of this simplified discussion, momentum is always conserved for collisions between balls.

To learn more about velocity refer to:

https://brainly.com/question/25749514

#SPJ4

The position of the oscillator at seconds is  ( A cos ( ω t + ϕ ) where A is the amplitude and ϕ is the initial phase and   f = 1/T = ω/2π.

Equilibrium or Mean Position: It is a state in which the body is in when there is no net force pushing against it. When a particle is oscillating, it is in its phase This is a representation of the particle's vibrational state at a particular instant.

The period of an oscillating system is the length of time it takes for a cycle to be completed. A system's period is a time measurement, and in physics, it's typically represented by the capital letter T. Although seconds are the most common, period is measured in time units relevant to that system.

Time, or T, is the oscillation's period, hence ωT = 2π or T = 2π/ω. The formula  f = 1/T = ω/2π. gives the reciprocal of the period, or the frequency f, in oscillations per second.

To know more about time period click:

https://brainly.com/question/26146342

#SPJ4

Answer:

a

Explanation:

As you add thermal energy the particles spread apart and are moving faster ..... a certain volume of water produces a much larger volume of steam as energy is added.....that is how steam engines work !

The correct expression for the resulting velocity is -1/2 vcar. The correct option is c.

The directional speed of an item in motion, as measured by a specific unit of time and observed from a certain point of reference, is what is referred to as velocity.

A car travels down a road at a certain velocity, is Vcar.

Let the initial velocity of the car travel downward be -V car

It is also, given, that the driver slows down so that the car is traveling only half as fast as before.

Resulting velocity = -1/2 vcar

Therefore, the correct option is c. -1/2vcar.

To learn more about velocity, refer to the link:

https://brainly.com/question/18084516

#SPJ1

Three helium-4 nuclei (alpha particles) are turned into carbon by a series of nuclear fusion processes known as the triple-alpha process.

What results from the triple-alpha procedure as the finished product?

The triple-alpha process and the alpha process are two classes of nuclear fusion reactions that stars use to change helium into heavier elements. The alpha process is also referred to as the alpha ladder. [1] Only helium is used in the triple-alpha process, which also yields carbon.

Which statement concerning alpha particles in an atom is accurate?

Two protons and two neutrons make up alpha particles, which are identical to helium nuclei and have a positive charge.

Learn more about Alpha Particle

Visit:

https://brainly.com/question/17464734

#SPJ4

Answer:

2515.7N

Explanation:

First step is to find the acceleration:

U = 0 and V =58.7 m/s

a = (V-U)/t

where, t = 3.5s

a = 58.7/3.5

so, in order to find the net force,

F= ma

= 150kg × 58.7/3.5

= 2515.7 N

The velocity on the narrow side is 11.6 m/s. This is the velocity of the water in the narrow part of the pipe.

To find the velocity of the water where the pipe is narrow, you can use the formula for the mass flow rate, which is given by:

Mass flow rate = Density * Flow rate

= Density * (Area * Velocity)

Where:

Density is the density of the fluid

Flow rate is the volume flow rate, or the rate at which volume flows through the pipe

Area is the cross-sectional area of the pipe

Velocity is the velocity of the fluid

The mass flow rate is constant, so you can set the mass flow rate on either side of the constriction equal to each other and solve for the velocity on the other side.

The cross-sectional area of the pipe on the narrow side is given by the formula for the area of a circle:

A = pi * r^2

Where:

A is the cross-sectional area of the pipe

r is the radius of the pipe

The radius of the pipe on the narrow side is 3 cm / 2 = 1.5 cm. Plugging this value into the formula for the cross-sectional area, you get:

A = pi * (1.5 cm)^2

= 7.07 cm^2

The cross-sectional area of the pipe on the wide side is given by the same formula, with a radius of 6 cm / 2 = 3 cm:

A = pi * (3 cm)^2

= 28.27 cm^2

Since the mass flow rate is constant, you can set the mass flow rates on either side of the constriction equal to each other and solve for the velocity on the other side:

(Density * 7.07 cm^2 * v) = (Density * 28.27 cm^2 * 8 m/s)

Solving for v, the velocity on the narrow side, you get:

v = (Density * 28.27 cm^2 * 8 m/s) / (Density * 7.07 cm^2)

= 11.6 m/s

The final value for the velocity on the narrow side is 11.6 m/s. This is the velocity of the water in the narrow part of the pipe.

To learn more about mass flow rate refer :

https://brainly.com/question/13289839

#SPJ4

The velocity of both objetcs after the collision is 3.07m/sec if both object masses are 6.2 kg and 8.0kg respectively.

To find the velocity of both objects we need to conserve the momentum. We need to follow the law of conservation of momentum which states that initial momentum is equal to final momentum.

Now, we know that momentum =mass × velocity

So, initial momentum of first object=6.2×3=18.6Kg-m/sec

Similarly, initial momentum of second object=8×3.5=28.0kg-m/sec

Now, it is given that both object stick together, so total mass of both objects are=(6.2+8)=14.2kg

Now, both objects are moving with common velocity, so assume both have velocity v

=>So, final momentum of both objects is =14.2×v

according to law of conservation of momentum

=>18.6+25=14.2v

=>43.6=14.2v

=>v=43.6/14.2

=>v=3.07m/sec

Hence, final velocity of objects are 3.07m/sec.

To know more about velocity, visit here:

https://brainly.com/question/18084516

#SPJ4

Most photons that leave the sun's surface have a surface temperature of 6,000 K, which corresponds to the visible light region of the electromagnetic spectrum.

The electromagnetic spectrum is a continuous range of wavelengths and frequencies that includes radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays. The wavelengths and frequencies of these different types of electromagnetic radiation are all different and correspond to different regions of the spectrum.

The visible light region of the electromagnetic spectrum is the portion of the spectrum that can be seen by the human eye. It ranges from about 400 nanometers (nm) to about 700 nm in wavelength, and corresponds to frequencies of about 7.5 x 10^14 Hz to about 4.3 x 10^14 Hz. Photons with wavelengths and frequencies in this range have enough energy to excite the photoreceptors in the human eye, allowing us to see them.

Learn more about Electromagnetic Spectrum here:

https://brainly.com/question/13803241

#SPJ4

The magnitude and location of the resultant force on the horizontal gate is: F = w * r * g, and Point A.

Magnitude is a measure of the size or intensity of a physical quantity. It is usually defined as the absolute value of the numerical value of the physical quantity, and is often expressed in terms of a unit of measurement. Magnitude can refer to a variety of different physical quantities, such as size, intensity, brightness, or energy. Magnitude can also refer to the relative size or intensity of two or more physical quantities, when compared to each other.

The resultant force on the horizontal gate is equal to the sum of the hydrostatic forces acting on the gate.
Since the gate is horizontal, the hydrostatic forces acting on the gate will be equal to the pressure difference between the top and bottom of the gate.
This pressure difference is equal to the product of the fluid density, gravitational acceleration, and the gate width.
Therefore, the magnitude of the resultant force on the gate will be:
F = w * r * g
The location of the resultant force on the gate will be at the center of the gate, which is point A.
Therefore, the magnitude and location of the resultant force on the horizontal gate is: F = w * r * g, and Point A.

To learn more about magnitude
https://brainly.com/question/24468862
#SPJ4

The major difference between what we've seen in discovered exoplanets and our own solar system is that extrasolar planet orbits tend to be closer and more eccentric than in our Solar System.

Exoplanet:

Any planet outside of our solar system is an exoplanet. The majority of exoplanets orbit other stars, while rogue planets—free-floating exoplanets that are unattached to any star—orbit the galactic center.

All of the planets in our solar system orbit around the Sun. Planets that orbit around other stars are called exoplanets.

Exoplanets are very hard to see directly with telescopes. They are hidden by the bright glare of the stars they orbit.

Learn more about exoplanets here

https://brainly.com/question/1514493

#SPJ4

The kinetic energy is 939.87 J.

Kinetic energy is the power that an object has as a result of motion. If we want to accelerate an object, we have to exert force. Applying force requires effort on our part. The object will be moving at a new, constant speed once the work is done because energy has been transferred to it.

A particle, an object, or a collection of particles can move because of kinetic energy, which is the force that drives motion. Kinetic energy is used by objects in motion like a person walking, a baseball being thrown, food falling from a table, and charged particles in an electric field.

Kinetic energy = 1/2mv²

Kinetic energy =  1/2×0.06×177²

Kinetic energy = 939.87 J.

To know more about kinetic energy visit:

https://brainly.com/question/26472013

#SPJ4

The system that is more energy efficient is system A because it makes use of electricity to produce more results.

Energy efficiency is the use of less energy to perform the same task or produce the same result.

Energy-efficient homes and buildings use less energy to heat, cool, and run appliances and electronics, and energy-efficient manufacturing facilities use less energy to produce goods.

Energy efficiency has the following benefits:

According to this question, the following applies:

Based on the above explanation, it can be observed that system A is more energy efficient because it uses the same electricity to achieve more.

Learn more about energy efficiency at: https://brainly.com/question/28939461

#SPJ1

Answer: 3 m/s^2

Explanation:

Acceleration equals change in velocity (speed) divided by total time.

a = (v2-v1)/t

a = (41 m/s - 20 m/s) / 7 s

a = 3 m/s^2

Mass is irrelevant in this question.

Answer:

5 m

Explanation:

Displacement is the straight-line distance from the starting point to the end point.  Student ends up 4m north and 3m west from where he started. Use pythagorean theorem to solve for displacement (d).  

d² = 3² + 4² = 25

d = [tex]\sqrt{25}[/tex] = 5 m

Or, if you remember from geometry, a right triangle with legs of 3 and 4 has a hypotenuse of 5 (3-4-5 right triangle)