Answer:
Option (a) is correct
Explanation:
The acceleration of an object is defined as the rate of change of velocity. Mathematically, it can be written as :
[tex]a=\dfrac{v-u}{t}[/tex]
Where
v and u are final and initial velocity
It is clear that if there is some change in velocity, it means the object is experiencing either acceleration or deceleration. Hence, the correct option is (a).
Answer:
a
Explanation:
Question 5 of 10
What are two things that happen when a home computer scanner uses
electromagnetic waves?
A. Red light shines on patterns of black and white, recording the
pattern of reflected light.
B. Objects are exposed to X-rays, which either pass through or are
absorbed by the objects.
C. A silicon chip releases electrons by the photoelectric effect,
producing an image.
D. A charge-coupled device captures visible light that is reflected off
an object
Answer: B. Objects are exposed to X-rays, which either pass through or are
absorbed by the objects.
C. A silicon chip releases electrons by the photoelectric effect,
producing an image.
Explanation:
A 2.0 kg sphere with a velocity of 6.0 m/s collides head-on and elastically with a stationary 10 kg sphere
Question: A 2.0 kg sphere with a velocity of 6.0 m/s collides head-on and elastically with a stationary 10 kg sphere, What is thier velocities after collision.
Answer:
v = 6 m/s, v' = 0 m/s
Explanation:
From the question,
For Elastic collision,
mu+m'u' = mv+m'v'......................... Equation 1
Where m = mass of the first sphere, m' = mass of the second sphere, u = initial velocity of the first sphere, u' = initial velocity of the second sphere, v = final veolocity of the first sphere, v' = final velocity of the second sphere.
Also,
The relative velocity before collision = relative velocity after collision
u-u' = v-v'............................ Equation 2
Given: m = 2 kg, m' = 10 kg, u = 6 m/s, u' = 0 m/s
Substitute into equation 1 and 2
2(6)+10(0) = 2v+10v'
2v+10v' = 12.............. Equation 3
6-0 = v-v'
v-v' = 6 ................... Equation 4
Solve equation 3 and 4 simultaneously.
v = 6+v'............. Equation 5
Substitute equation 5 into equation 3
2(6+v')+10v' = 12
12+2v'+10v' = 12
12v' = 12-12
v' = 0/12
v' = 0 m/s.
Also substitute the value of v' into equation 5
v = 6+0
v = 6 m/s
The semi-major axis of this ellipse is 8.8 cm, and the distance from one of the foci to the
center is 4.4 cm. What is the eccentricity of the ellipse?
The eccentricity is 0.5
Is sodium chloride a reactant
Answer:
yes it is a reactant
What is the color of lava at its hottest? Help asap
1. What is the magnitude of the force on a charge of +40 μC that is 0.6 m from a charge of - 80 μC?
Answer:
The magnitude of the force is 79.893 N.
Explanation:
The magnitude of the electrostatic force between the two particles is determined by Coloumb's Law, whose formula is:
[tex]F = \frac{\kappa \cdot |q_{A}|\cdot |q_{B}|}{r^{2}}[/tex] (1)
Where:
[tex]\kappa[/tex] - Electrostatic constant, in newtons-square meters per square coulomb.
[tex]q_{A}, q_{B}[/tex] - Electric charges, in coulombs.
[tex]r[/tex] - Distance, in meters.
If we know that [tex]\kappa = 8.988\times 10^{9}\,\frac{N\cdot m^{2}}{C^{2}}[/tex], [tex]q_{A} = +40\times 10^{-6}\, C[/tex], [tex]q_{B} = - 80\times 10^{-6}\, C[/tex] and [tex]r = 0.6\,m[/tex], then the magnitude of the force is:
[tex]F = \frac{\kappa \cdot |q_{A}|\cdot |q_{B}|}{r^{2}}[/tex]
[tex]F = 79.893\,N[/tex]
The magnitude of the force is 79.893 N.
If spring has a spring constant of 500 N/m and is stretched .50 meters,how much energy is stored in the spring ((show work for full credit, show equation))
Answer:
The energy stored is: 62.5 Joules
Explanation:
Given
[tex]k = 500N/m[/tex] --- spring constant
[tex]x = 0.5m[/tex] --- stretch
Required
The amount of energy
This is calculated as:
[tex]U = \frac{1}{2} kx^2[/tex]
[tex]U = \frac{1}{2} * 500N/m * (0.5m)^2[/tex]
[tex]U = 250N/m * (0.5m)^2[/tex]
[tex]U = 62.5\ J[/tex]
A man's higher initial acceleration means that a man can outrun a horse over a very short race. A simple - but plausible - model for a sprint by a man and a horse uses the following assumptions: The man accelerates at 6.0 m/s2for 1.8 s and then runs at a constant speed. A horse accelerates at a more modest 5.0 m/s2 but continues accelerating for 4.8 s and then continues at a constant speed. A man and a horse are competing in a 200 m race. The man is given a 100 m head start, so he begins 100 mfrom the finish line.
How much time does it take the man to finish the race? The horse? Who wins?
Answer:
t_man = 10.16 s, t_horse = 10.73 s, the winner is the man
Explanation:
To solve this problem we are going to find the time of each one separately.
Man we look for distance and time during acceleration
x₁ = v₀ t₁ + ½ a₁ t₁²
as it comes out of rest its initial velocity is zero
x₁ = ½ a₁ t₁²
x₁ = ½ 6.0 1.8²
x₁ = 9.72 m
at this point its speed is
v₁ = v₀ + a t
v₁ = 0 + 6 1.8
v₁ = 10.8 m / s
From here on it continues at constant speed, the distance that the man needs to travel from the point where the man leaves at 100m is
x₂ = 100 - x₁
x₂ = 100- 9.72
x₂ = 90.28 m
the time for this part is
v₁ = x₂ / t₂
t₂ = x₂ / v₂
t₂ = 90.28 / 10.8
t₂ = 8.36 s
the total time for the man is
t_man = t₁ + t₂
t _man = 1.8 + 8.36
t_man = 10.16 s
We repeat the calculation for the horse
distance traveled during the acceleration period
x₃ = v₀ t + ½ a₂ t₃²
as part of rest its initial velocity is zero
x₃ = ½ a₂ t₃²
x₃ = ½ 5.0 4.8²
x₃ = 57.6 m
the velocity at this point is
v₃ = v₀ + a₂ t₃
v₃ = 0 + 5 4.8
v₃ = 24 m / s
the rest of the route is at constant speed, the remaining distance
x₄ = 200 - x₃
x₄ = 200 - 57.6
x₄ = 142.4 m
the time to go through it is
t₄ = x₄ / v₃
t₄ = 142.4 / 24
t₄ = 5.93 s
the total time for the horse is
t_horse = t₃ + t₄
t_horse = 4.8 + 5.93
t_horse = 10.73 s
when we compare the times we see that the man arrives a little before the horse, the winner is the man
Which is used to zero a triple beam balance
A.
the pan
B.
a rider
C.
a beam
D.
the tare knob
John has an object suspended in the air. It has a mass of 50 kilograms and is 50 meters above the ground. Calculate the object's potential energy?
The equivalent resistance in a series circuit is found by ____
the resistances of all the resistors.
A. multiplying
B. comparing
C. adding the reciprocals of
D. adding
Explanation:
In a series circuit the equivalent resistance is the algebraic sum of the resistances.
A car hits a wall with a force of 80 N and
has a mass of 4.5 kg. What was the
acceleration of the car?
Please help please real quick
Answer:
1. (a) The final velocity is 20 m/s
(b) The distance travelled is20 meters
2. The distance travelled by the train in the 30 seconds is 825 meters
3. The most correct option is;
(d) 53 km
4. The heat, developed by the electric iron is 15,000 joules
5. a) In the first network the resistance between A and B is 2 Ω
b) In the second network the resistance between A and B is 4Ω
c) In the third network the resistance between A and B is 6Ω
d) In the fourth network the resistance between A and B is 2Ω
Explanation:
1. (a) The parameters of the cheetahs motion are;
The initial motion (velocity) of the cheetah = 0 m/s (The cheetah starts from rest)
The acceleration of the cheetah, a = 2 m/s²
The duration of the acceleration of the cheetah, t = 10 seconds
The kinematic equation of the motion of uniform acceleration, of the cheetah can be written in the following form;
v = u + a·t
s = u·t + 1/2·a·t²
Where;
v = The final velocity
u = The initial velocity = 0 m/s
a = The acceleration of the cheetah = 2 m/s²
s = The distance traveled
∴ v = 0 + 2 × 10 = 20
The final velocity, v = 20 m/s
(b) From s = u·t + 1/2·a·t², we have;
s = 0 × 10 + 1/2 × 10 × 2² = 20
The distance travelled, s = 20 meters
2. The given details of the motion of the train are;
The initial velocity of the train, u = 20 m·s⁻¹
The acceleration of the train, a = 0.5 m·s⁻²
The duration of the train's acceleration, t = 30 seconds
Therefore, the distance travelled, 's', is given by; s = u·t + 1/2·a·t²
∴ s = 20 × 30 + (1/2) × 0.5 × 30² = 825
The distance travelled by the train in the 30 seconds, s = 825 meters
3. The given distance the truck covers with the average speed of 80 km/h, d₁ = 40 km
The distance the truck then covers with the average speed of 40 km/h, d₂ = 40 km
[tex]Average \ speed = \dfrac{Total \ distance}{Time}[/tex]
[tex]\therefore time, \, t = \dfrac{Total \ distance}{Average \ speed}[/tex]
The time it takes the truck to cover the 40 km at 80 km/h = 40 km/(80 km·h) t₁ = 0.5 hour
The time it takes the truck to cover the 40 km at 80 km/h = 40 km/(40 km·h) t₂ = 1 hour
The total time taken to cover both 40 km distances, t = t₁ + t₂
∴ The total time taken to cover both 40 km distances, t = (0.5 + 1) hour = 1.5 hours
The total distance covered at both speeds, d = d₁ + d₂
∴ d = 40 km + 40 km = 80 km
The average speed of the truck for the total distance, [tex]v_{average}[/tex] = d/t
∴ [tex]v_{average}[/tex] = 80 km/1.5 hours = 53.[tex]\overline 3[/tex] km/h ≈ 53 km/h
The average speed of the truck for the total distance, [tex]v_{average}[/tex] ≈ 53 km/h
The correct option is (d) 53 km
4. The heat, 'H', developed by the electric iron is given by the following formula;
H = I²·R·t
Where;
I = The current flowing in the electric iron = 5 A
R = The resistance of the iron = 20Ω
t = The time duration of the flow of the current = 30 s
∴ H = (5 A)² × 20 Ω × 30 s = 15,000 joules
The heat, developed by the electric iron, H = 15,000 joules
5. Let 'R' represent the resistance between A and B in each network
a) For the first network, we have;
1/R = 1/(2 + 2) + 1/(2 + 2) = 1/4 + 1/4 = 1/2
∴ R = 2 Ω
∴ The resistance between A and B is 2 Ω
b) For the second network, we have;
R = 1/(1/2 + 1/2) + 3 = 4
R = 4Ω
∴ The resistance between A and B is 4 Ω
c) For the third network, we have;
R = 2 + 1/(1/4 + 1/4) + 2 = 6
R = 6Ω
∴ The resistance between A and B is 6 Ω
d) For the fourth network, we have;
R = 1/(1/2 + 1/2) + 1/(1/2 + 1/2) = 2
R = 2Ω
∴ The resistance between A and B is 2 Ω
A proton travels through uniform magnetic and electric fields. The magnetic field is in the negative x direction and has a magnitude of 2.48 mT. At one instant the velocity of the proton is in the positive y direction and has a magnitude of 1840 m/s. At that instant, what is the magnitude of the net force acting on the proton if the electric field is (a) in the positive z direction and has a magnitude of 5.19 V/m, (b) in the negative z direction and has a magnitude of 5.19 V/m, and (c) in the positive x direction and has a magnitude of 5.19 V/m
Answer:
a) F = 15.6 10⁻¹⁹ k^ N, b) F = -1 10⁻¹⁹ k^ N,
c) F = (8.3 i^ + 73 k^) 10⁻¹⁹ N
Explanation:
In this exercise we calculate the magnetic and electric force separately.
Let's start by calculating the magnetic force
F_m = q v x B
where bold letters indicate vectors, the modulus of this expression is
F_m = q v B
the direction is given by the right hand rule, where the thumb points in the direction of velocity, the fingers are extended in the direction of the magnetic field and the palm is in the directional ne force if the charge is positive
let's calculate the magnitude
F_m = 1.6 10⁻¹⁹ 1840 2.48 10⁻³
F_m = 7.3 10⁻¹⁹ N
we calculate the direction, the thumb is in the direction of + y,
fingers extended in the direction of -ax
the palm remains + z
therefore the magnetic force is in the direction of the positive side of the z axis
The electric force is
F_e = q E
give several possibilities for the electric field
a) electric field E = 5.19 V / m in the direction of + z
we calculate
F_e = 1.6 10⁻¹⁹ 5.19
F_e = 8.3 10⁻¹⁹ N
the total force is
F = F_m + F_e
F = (8.3 k ^ + 7.3 k ^) 10⁻¹⁹
F = 15.6 10⁻¹⁹ k^ N
b) in the -z direction
F_e = -8.3 10⁻¹⁹ k^ N
F = Fm + Fe
F = (-8.3 k ^ + 7.3 k ^) 10⁻¹⁹
F = -1 10⁻¹⁹ k^ N
c) in the + x direction
F_e = 8.3 10⁻¹⁹ i^ N
the total force is
F = (8.3 i^ + 73 k^) 10⁻¹⁹ N
who won the 2020-2021 Nfl Mvp Award
Answer:
During a star-studded but socially safe ceremony for the 10th Annual NFL Honors, Green Bay Packers quarterback Aaron Rodgers earned the prestige of being the 2020 NFL Most Valuable Player (MVP).
A Yellow Giant is a luminous giant star of approximately 85 times brighter than the surface of the Earth’s Sun. The color is Orange and have a surface temperature of 5400 K. True or false? Answer Fast Please.
Answer:
the statement is FALSE
Explanation:
To answer this question we use that thermodynamic energy is
E = K T
also according to the Planck relation
E = h f
the speed of light et related to frequencies and wavelength
c = λ f
f = c /λ
we substitute
hc /λ = KT
λ= hc / k T
calculate us
lam = 6.62 10⁻³⁴ 3 10⁸ / 1.381 10⁻²³ 5400
lam = 2,663 10⁻⁸ m
let's reduce to num
lam = 2,663 10
lam = 26,63 nm
This wavelength is in the farultraviolet, therefore the statement is FALSE
Which of the following best describes the circuit shown below?
A. Short
B. Combination
C. Series
D. Parallel
Answer:
The answer is C. Series.
If a body carries a charge of +3 C, then which of the following is true?
а) It has an excess of 4.8 x 10^19 electrons
b) It has an excess of 1.87 x 10^19 electrons *1019
C) It is deficit of 1.87 x 10^19 electrons
d) It is deficit of 4.8 x 10^19 electrons
Answer: C) it is deficit of 1.87 x 10^19 electrons
Explanation:
how do you select the appropriate tools for caregiving rated task effectively?
Answer:
Care giving tools like medical devices or any medical supplies which aid the effectiveness of care for the patient will help the quality of work of care giving. ... All of the care giving tool should also be efficient and effective
takes 5 seconds and 2,000 J for a crane to lift a very heavy object. Which of these correctly describes power and energy for this action?
2,000 J of energy was converted into some other energy, requiring 10,000 W of power.
2,000 J of energy was converted into some other energy each second, requiring 400 W of power
2,000 J of power was converted into 400 W of energy.
2,000 J of power was converted into some other power every second, requiring 10,000 W of energy.
A crane takes 5 s and 2,000 J to lift an object. That is, 2,000 J of energy was converted into some other energy each second, requiring 400 W of power.
What is power?In physics, power is the amount of energy transferred or converted per unit time.
A crane uses 2,000 J of energy (E) to perform work (W) is 5 s (t). Let's calculate the power used (P).
P = W / t = 2,000 J / 5 s = 400 W
Which of these correctly describes power and energy for this action?
2,000 J of energy was converted into some other energy, requiring 10,000 W of power. No, the required power was 400 W.2,000 J of energy was converted into some other energy each second, requiring 400 W of power. Yes.2,000 J of power was converted into 400 W of energy. No, energy cannot be converted into power.2,000 J of power was converted into some other power every second, requiring 10,000 W of energy. No, the required power was 400 W.A crane takes 5 s and 2,000 J to lift an object. That is, 2,000 J of energy was converted into some other energy each second, requiring 400 W of power.
Learn more about power here: https://brainly.com/question/911620
#SPJ1
Energy can come from electricity, but it
can also come from water
false
true
Answer:
the answer is truth
Explanation:
Answer:
I think it might be true...
Can someone please help me with science.
On the dog's return trip (between t = 10 and t = 12.5 seconds), the slope of the position function is steeper than during the first 5 seconds, which means the dog ran home faster. The only option that captures this is D.
You can check to make sure that the dog indeed runs twice as fast on the return trip. The slope of the position function during the first 5 seconds is
(change in position) / (change in time) = (5 - 0) / (5 - 0) = 5/5 = 1
while during the return trip, it is
(0 - 5) / (12.5 - 10) = -5/2.5 = -2
Ignoring the sign (which only indicates the direction in which the dog was running), we see that the dog's speed on the return trip was indeed twice as high as during the first 5 s.
The National Aeronautics and Space Administration (NASA) studies the physiological effects of large accelerations on astronauts. Some of these studies use a machine known as a centrifuge. This machine consists of a long arm, to one end of which is attached a chamber in which the astronaut sits. The other end of the arm is connected to an axis about which the arm and chamber can be rotated. The astronaut moves on a circular path, much like a model airplane flying in a circle on a guideline. The chamber is located 20.0 m from the center of the circle. At what speed must the chamber move so that an astronaut is subjected to 5.64 times the acceleration due to gravity
Answer:
w = 1,662 rad / s, v = 33.25 m / s
Explanation:
This this exercise indicates that the acceleration felt by the astronauts is
a = 5.64 g
in a circular motion the centripetal acceleration is
a_c = v²/ r
angular and linear variables are related
v = w r
we substitute
a_c = w² r
we finally have
5.64 g = w² r
w² = 5.64 g / r
let's calculate
w = [tex]\sqrt{ \frac{5.64 \ 9.8}{20.0} }[/tex]
w = 1,662 rad / s
linear velocity is
v = w r
v = 1,662 20
v = 33.25 m / s
7. Thermal energy depends upon the______ and _____ of an object?
:
Please give me brainly,
The thermal energy of an object depends on three things: 4 the number of molecules in the object 4 the temperature of the object (average molecular motion) 4 the arrangement of the object's molecules (states of matter). The more molecules an object has at a given temperature, the more thermal energy it has.
Mass and Temperarture
I am pretty sure that is right if Not sorry
Have a great day.
A 20-gram bullet traveling at 250 m/s strikes a block of wood that weighs 2 kg. With what velocity will the block and bullet move after the collision? [convert g to kg]
Answer:
the velocity of the bullet-wood system after the collision is 2.48 m/s
Explanation:
Given;
mass of the bullet, m₀ = 20 g = 0.02 kg
velocity of the bullet, v₀ = 250 m/s
mass of the wood, m₁ = 2 kg
velocity of the wood, v₁ = 0
Let the velocity of the bullet-wood system after collision = v
Apply the principle of conservation of linear momentum to calculate the final velocity of the system;
Initial momentum = final momentum
m₀v₀ + m₁v₁ = v(m₀ + m₁)
0.02 x 250 + 2 x 0 = v(2 + 0.02)
5 + 0 = v(2.02)
5 = 2.02v
v = 5/2.02
v = 2.48 m/s
Therefore, the velocity of the bullet-wood system after the collision is 2.48 m/s
Which of the following ways of writing 1000w is incorrect?
1) 1 kW
2) 1 x 10³ W
3) 10 x 10³ W
4) 1.0 x 10³ W
Answer:
the third one is incorrect
Explanation:
10 x 10³= 10^1 x 10^3 = 10^4
Define the term kinetic frictional force
Answer:Kinetic friction is defined as a force that acts between moving surfaces. A body moving on the surface experiences a force in the opposite direction of its movement. The magnitude of the force will depend on the coefficient of kinetic friction between the two material.
Explanation:
a transfer of energy without a transfer of mass describes what?
Explanation:
Wave motion
ex...longitudinal wave.
Which of the following skills that you learn while participating in a team sport is also a life skill that employers look for?
A.
Showing respect to others
B. Working well with others
c.
Problem solving
D
All of the above
Answer:
The answer is all of the above
Explanation:
Answer:
D
Explanation:
Imagine you leave the dock on a fishing boat that travels east for 30 kilometers when the captain realizes he left the fishing rods on the dock. It takes him 40 minutes to travel out against the current but only 20 minutes to return to the dock.
Answer:
Average speed is 60 km/hr whereas average velocity is 0 km/ hr.
Explanation:
The average speed of the boat is 60 km/ hr while on the other hand, the average velocity of the boat is 0 km/ hr because average speed is the total distance covered by the boat in total time and average velocity is the displacement covered by the boat in total time. The total distance covered by the boat is 60 km and the total time is 60 minutes which is equals to one hour so the answer is 60 km/hr whereas the displacement is the shortest distance between initial and final position which is 0 in this case so 0 divided by 60 minutes or one hour is also 0.