Split up the forces into components acting parallel to and perpendicular to the slope. See the attached picture for the reference axes.
The box stays on the surface of the plane, so that the net force acting perpendicular to it is 0, and the only acceleration is applied in the parallel direction.
Let m be the mass of the box, θ the angle the plane makes with the ground, and a the acceleration of the box. By Newton's second law, we have
• net parallel force
∑ Force (//) = W (//) - F = m a
(that is, the net force in the parallel direction is the sum of the parallel component of the weight W and the friction F which acts in the negative direction)
• net perpendicular force
∑ Force (⟂) = W (⟂) + N = 0
Notice that
W (//) = W sin(θ) … … … which is positive since it points down the plane
W (⟂) = -W cos(θ) … … … which is negative since it points opposite the normal force N
So the equations become
W sin(θ) - F = m a
-W cos(θ) + N = 0
Solving for a gives
a = (W sin(θ) - F ) / m
which is good enough if you know the magnitude of the friction force.
If you don't, you can write F in terms of the coefficient of kinetic friction between the box and plane, µ, as
F = µ N
so that
a = (W sin(θ) - µ N ) / m
and the normal force itself has a magnitude of
N = W cos(θ)
so that
a = (W sin(θ) - µ W cos(θ) ) / m
The weight W has magnitude m g, where g is the magnitude of the acceleration due to gravity, so
a = (m g sin(θ) - µ m g cos(θ) ) / m
a = g (sin(θ) - µ cos(θ))
A. A piece of paper near a magnet
B. An aluminum nail near a magnet
C. An iron nail, not near a magnet
D. An iron nail near a magnet
Answer:
it’s c not d
Explanation:
took the test
Answer: D!!!
Explanation: jus got it wrong from the other answer.
A statement of the second law of thermodynamics is that:__________.
a) spontaneous reactions are always exothermic.
b) energy is conserved in a chemical reaction that has a decrease in entropy.
c) spontaneous reactions are always endothermic.
d) in a spontaneous process, the entropy of the universe increases.
Answer:
in a spontaneous process, the entropy of the universe increases.
Explanation:
Entropy is a measure of of the degree of randomness or disorderliness in a system.
The second law of thermodynamics can be stated as follows; "in any spontaneous process, the entropy of the universe increases."
The universe here refers to the system's disorder and the disorder of the surroundings. Therefore, a spontaneous process can occur, in which the entropy of the system decreases, only if the entropy increases in the surroundings.
For instance, when ice freezes, the entropy of liquid water decreases, that is, the entropy of the system decreases. However, heat is given off to the surroundings and the entropy of the surroundings increases. This is an obvious expression of this law.
A monatomic ideal gas with an initial pressure of 500 kPa and an initial volume of 1.80 L expands isothermally to a final volume of 5.20 L. How much work is done on the gas in this process?
A) 1700J
B) 875J
C) 1570J
D) 900J
E) 955J
Answer:
955 J
Explanation:
PV = nRT
500 x 10³ x 1.8 x 10⁻³ = nRT
= 900 J
work done by gas in isothermal expansion
= nRT lnV₂ / V₁
= 900 ln 5.2 / 1.8
= 900 x ln 2.89
= 900 x 1.06
= 955 J
A merry-go-round on a playground consists of a horizontal solid disk with a weight of 805 N and a radius of 1.58 m. A child applies a force 49.5 N tangentially to the edge of the disk to start it from rest. What is the kinetic energy of the merry-go-round disk (in J) after 2.95 s?
Answer:
The value is [tex]KE = 259.6 \ J[/tex]
Explanation:
From the question we are told that
The weight of the horizontal solid disk is [tex]W = 805 \ N[/tex]
The radius of the horizontal solid disk is [tex]r = 1.58 \ m[/tex]
The force applied by the child is [tex]F = 49.5 \ N[/tex]
The time considered is [tex]t = 2.95 \ s[/tex]
Generally the mass of the horizontal solid disk is mathematically represented as
[tex]m_h = \frac{W}{ g}[/tex]
=> [tex]m_h = \frac{805}{ 9.8 }[/tex]
=> [tex]m_h = 82.14 \ N[/tex]
Generally the moment of inertia of the horizontal solid disk is mathematically represented as
[tex]I = \frac{1}{2} * m * r^ 2[/tex]
=> [tex]I = \frac{1}{2} * 82.14 * 1.58^ 2[/tex]
=> [tex]I = 102.5 \ kg \cdot m^2[/tex]
Generally the net torque experienced by the horizontal solid disk is mathematically represented as
[tex]T = I * \alpha = F * r[/tex]
=> [tex]\alpha = \frac{ F * r }{ I }[/tex]
=> [tex]\alpha = \frac{ 49.5 * 1.58 }{ 102.53 }[/tex]
=> [tex]\alpha = 0.7628[/tex]
Gnerally from kinematic equation we have that
[tex]w = w_o + \alpha t[/tex]
Here [tex]w_o[/tex] is the initial angular velocity velocity of the horizontal solid disk which is [tex]w_o = 0\ rad/s[/tex]
So
[tex]w = 0 + 0.7628 * 2.95[/tex]
=> [tex]w = 2.2503 \ rad/s[/tex]
Generally the kinetic energy is mathematically represented as
[tex]KE = \frac{1}{2} * I * w^2[/tex]
=> [tex]KE = \frac{1}{2} * 102.53 * 2.2503 ^2[/tex]
=> [tex]KE = 259.6 \ J[/tex]
In the past, Africa used to be further away from Europe than it is now
(shown below). What could explain why Africa is closer to Europe now than
it was before? *
Answer: Plates shifting
Explanation: After years and years of plates colliding into solid rock, they slowly become closer together. As recent studies have shown, Africa is currently moving closer to Europe one centimeter every year (one inch every 2.5 years).
Answer:
nvudbwasivnjlscv bwbfvsz
Explanation:
The glowing dot represents the transmission of a nerve impulse along the nerves that make up the neural pathway. A nerve impulse is an electrical signal that travels from one nerve cell to another.
Which part of the brain processes this signal?
Answer:
The answer is "Cerebral Cortex"
Explanation:
The neurotransmitter diffuses across the short distance of the synapse and ties to a receptor protein of the objective neuron. At the point when the sub-atomic sign ties to the receptor, the cell film of the objective neuron changes its electrical state and another evaluated expected starts. On the off chance that that evaluated potential is sufficiently able to arrive at limit, the subsequent neuron produces an activity potential at its axon hillock. The objective of this neuron is another neuron in the thalamus of the mind, the piece of the CNS that goes about as a transfer for tactile data.
At another neurotransmitter, synapse is delivered and ties to its receptor. The thalamus at that point sends the sensory information to the cerebral cortex, the furthest layer of dark issue in the brain, where cognizant view of that water temperature starts.
A region of the cortex is particular for imparting signs down to the spinal cord for development. The upper engine neuron is in this area, called the precentral gyrus of the frontal cortex, which has an axon that broadens right down the spinal cord. At the degree of the spinal cord at which this axon makes a neurotransmitter, a reviewed potential happens in the cell membrane of a lower engine neuron.
1. The mass of the Earth is 81 times the mass of the Moon. Using Newton's Law of Gravity, what would the effect of gravitation be if the mass of the Moon were increased by four times and the distance between Earth and
the Moon were cut in half?
Answer:
effects of gravity on the Moon and Earth
Explanation: Newton found the Moon's inward acceleration in its orbit to be 0.0027 metre per second per second, the same as (1/60)2 of the acceleration of a falling object at the surface of Earth.
HELP!!!!This question is typical on some driver's
license exams: A car moving at 49 km/h skids
12 m with locked brakes.
How far will the car skid with locked brakes
at 122.5 km/h? Assume that energy loss is
due only to sliding friction.
Answer in units of m.
Answer:
d=75 m
Explanation:
Before Skidding
[tex]v^2-v_o^2=2ad[/tex]
[tex]0^2-49^2=2a(12)[/tex]
After Skidding
[tex]v^2-v_o^2=2ad[/tex]
[tex]0^2-122.5^2=2ad[/tex]
[tex]\frac{49^2}{122.5^2}=\frac{12}{d}[/tex]
[tex]d=75 m[/tex]
Hope it helps
what is the need of force in our life
Answer:
A force is a push or a pull and it affects our daily lives because without force,people would not be able to open and close stuff or lift up our arms or legs .....or anything, for that matter.
Explanation:
brainly
3
4
Lucy runs 4 meters to the east, then 5 meters south. What is the magnitude of her displacement?
Show Your Work
Answer:
The displacement is 6.4m
Explanation:
Step one:
given
we are told that Lucy runs 4 meters to the east,
then 5 meters south.
let the distance east be the displacement in the x-direction, and south be the y-direction
Step two:
The resultant of the x and y displacement is the magnitude of the total displacement z
applying Pythagoras theorem we have
z=√x^2+y^2
z=√4^2+5^2
z=√16+25
z=√41
z=6.4m
d. If a dog has a mass of 12 kg, what is its weight on Neptune?
11.7N/kg
Answer:
133.8 N
Explanation:
Recall that the acceleration of gravity in Neptune is estimated as 11.15 m/s^2
Therefore, the weight of the dog on this planet would be:
Weight = mass x acceleration of gravity = 12 kg x 11.15 m/s^2 = 133.8 N
A golf ball flies through the air after being struck with a golf club. Which of the following statements describes the force on the ball as momentum is transferred between the club and ball?
A. The ball does not experience any force.
B. The force experienced by the ball is greater than the force experienced by the club.
C. The force experienced by the ball equals the force experienced by the club.
D. The force experienced by the ball is weaker than the force experienced by the club.
Answer:
C) The force experienced by the ball equals the force experienced by the club.
Explanation:
When the golfer strikes the ball with his club, the club exerts a force on the ball. Due to Newton's Third Law Of Motion [Every Action has an equal and opposite reaction], the ball also exerts an equal force on the club. However,
As the mass of the club is usually greater than the mass of the ball, it accelerates slower; While the ball way faster, following the equation : F=ma
John decided to cycle to his friend's house at a speed of 5km/h and the journey took 2
hours. How far did John cycle?
Answer:100 miles
Explanation:
Answer:
10 Km
Explanation:
He is going 5km per hour and he arrived at his friend's house in 2 hours. You multiply 5 by 2 and you get 10.
A 1.00-m3 object floats in water with 30.0% of its volume above the waterline. What does the object weigh out of the water?
Answer:
Object's weight = 6,839.42 N
Explanation:
Given
Above waterline = 30%
Volume of object = 1m^3
Required
Determine the weight of the object
First, we need to calculate its Mass
Mass = Density of Water * Volume of object in water
Density of water = 997kg/m³
If 30% is above waterline, then 70% is in water.
So:
Mass = Density of Water * Volume of object in water
Mass = 997kg/m³ * 70%m³
Mass = 997kg * 70%
Mass = 697.9 kg
The object weight sis then calculated as thus:
Weight = Mass * Acceleration of gravity
Weight = 697.9 kg * 9.8m/s²
Weight = 6 839.42 N
A certain heat engine does 30.2 kJ of work and dissipates 9.14 kJ of waste heat in a cyclical process.
A) What was the heat input to this engine?
B) What was its efficiency?
Answer:
a) [tex]H_{in}=39.34 kJ[/tex]
b) Efficiency=76.77%
Explanation:
a)
In order to solve this problem, we can use the following formula:
[tex]H_{in}=H_{out}+W[/tex]
the problem provides us with all the necessary information so we can directly use the formula:
[tex]H_{in}=9.14kJ+30.2kJ[/tex]
[tex]H_{in}=39.34 kJ[/tex]
b) In order to find the efficiency, we can use the following formula:
[tex]Efficiency=\frac{W}{H_{in}}*100\%[/tex]
so we get:
[tex]Efficiency=\frac{30.2kJ}{39.34kJ}*100\%[/tex]
Efficiency=76.77%
What is the magnitude of the centripetal force that must be applied in order for a 2kg ball on a 2.0 m string to spin with uniform circular motion at 5.0 m/s
The ball needs to accelerate with a magnitude a (pointed towards the center of the circle) of
a = (5.0 m/s)² / (2.0 m) = 12.5 m/s²
Then the required tension F in the string would need to be
F = (2 kg) (12.5 m/s²) = 25 N
A rocket will move upward as long as which condition applies?
Which of the following statements are true of cancer types? Check all that apply. --
- Cancer is named according to the color the cells turn.
- Skin cancer is considered a very common type of cancer.
- Cancer is often named according to what body type it affects.
- Skin cancer is the least common type of cancer.
the answer is cancer is often named according to what body type it affects
Answer:
B,C
Explanation:
skin cancer is considered a very common type of cancer. Cancer is often named accordingly to a body type it affects.
Which change in an object would increase the force needed to move the object?
А.
decreasing the velocity of an object
B
increasing the volume of an object
с
decreasing the mass of an object
D
increasing the mass of an object
Answer:
D i think
Explanation:
Heavier objects (objects with more mass) are more difficult to move and stop.
Answer:
Increasing the mass of the object (option D in the list of answers)
Explanation:
Recall that F = m x a
therefore, if the mass increases, the force increases
A horse has a momentum of 1200 kg·m/s. If the horse has a mass of 313 kg, what is the speed of the horse?
Answer:
3.83 m/sExplanation:
The speed of the horse can be found by using the formula
[tex]v = \frac{p}{m} \\ [/tex]
p is the momentum
m is the mass
From the question we have
[tex]v = \frac{1200}{313} \\ = 3.83386..[/tex]
We have the final answer as
3.83 m/sHope this helps you
Which of the following is not an example of work being done on an object?
Pushing on a rock that will not move
Paddeling a canoe down a river
Lifting a bag of groceries
Throwing a ball across a field
Answer:
Lifting a bag of groceries
Answer:
paddeling a canoe down a river :D or throwing a ball across a field
Explanation:
A hare can run at a rate of 15 m/s, while a turbocharged tortoise can now crawl at a rate of 3 m/s, how much of a head-start (time-wise) does the tortoise need in order to tie the hare in a 250 meter race?
A.
16.7 seconds
B.
66.7 seconds
C.
83.3 seconds
D.
100 seconds
Answer:
t = 66.7 s
Explanation:
Given that,
Speed of a hare, v = 15 m/s
Speed of a turbocharged tortoise, v' = 3 m/s
The hare in a 250 meter race
Let the Hare takes time t. It can be calculated as follows :
[tex]t=\dfrac{250}{15}=16.67\ s[/tex]
Let a turbocharged tortoise takes t'. It can be calulated as follows :
[tex]t'=\dfrac{250}{3}= 83.33\ s[/tex]
To tie the race, required time is given by :
[tex]\Delta t = t'-t\\\\=83.33-16.67\\\\=66.66\ s\\\\\approx 66.7\ s[/tex]
Hence, the correct option is (b) i.e. 66.7 seconds.
While getting buff at the gym you lift a bunch of weights applying 1000N of force to lift them from the ground to a height of 2m. How much work did you do?
A. 2000 J
B. 1000J
C. -2000 J
D. -1000 J
This diagram shows a baseball’s motion.
A baseball is shown at 5 positions along an arc from left to right. A is far left and C is center, with B halfway between A and C. E is far right with D halfway between C and E.
Which statement is best supported by the diagram?
Kinetic energy becomes potential energy between points R and S.
Maximum potential energy is at point P.
Maximum potential energy is at point R.
Potential energy becomes kinetic energy between points P and Q.
Answer:
c
Explanation:
Maximum potential energy is at point R is best supported by the diagram. Therefore, the correct option is option C among all the given options.
What is motion?In physics, motion is a function of a body's position or orientation over time. Translation is defined as movement across a line or even a curve. Rotation is a motion that modifies a body's orientation. In all scenarios, the acceleration and directed speed of every point on the body are equal (time rate of change of velocity).
Every movement has a frame of reference to which it is related. A body isn't in motion when it is said to be at rest; rather, it is being characterized in relation to a reference frame that's also moving with the body. Maximum potential energy is at point R is best supported by the diagram.
Therefore, the correct option is option C.
To learn more about motion, here:
https://brainly.com/question/3421105
#SPJ6
A 12 kg coyote runs towards a rabbit in the Ortega Mountains
with a velocity of 8 m/s. Determine the momentum of the
coyote.
What is "given" in the word problem?
A) mass and velocity
B) momentum
C) momentum and mass
D) momentum and velocity
Given :
A 12 kg coyote runs towards a rabbit in the Ortega Mountains with a velocity of 8 m/s.
To Find :
The momentum of the coyote.
Solution :
The given in the question is mass of coyote which is 12 kg and velocity which is 8 m/s .
Momentum is given by :
M = mass × velocity
M = 12 × 8 kg m/s
M = 96 kg m/s
Hence, this is the required solution.
pplzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz helppppp
Answer:
D. The airplane will turn towards the east
Explanation:
If the airplane is thrown straight towards the north, the window which is moving from left (west) to right (east) the wind will knock the plane towards the right (east) since thats the way it is blowing.
A 60-kg jogger runs up a long flight of
stairs in 4.0 s. The vertical height of the
stairs is 4.5 m.
a. Estimate the jogger's power
output in watts and horsepower.
b. How much energy did this
require?
Explanation:
Given parameters:
Mass of Jogger = 60kg
Time = 4s
Vertical height = 4.5m
Unknown:
Jogger's power output = ?
Energy required = ?
Solution:
The power output of the jogger is defined as the rate at which work is done.
Power = [tex]\frac{force x distance}{time}[/tex]
Now insert the parameters and solve;
Work done = Force x distance = mgh
m is the mass
g is the acceleration due to gravity = 9.8m/s²
h is the height
Work done = 60 x 9.8 x 4.5 = 2646J
Power = [tex]\frac{2646}{4}[/tex] = 661.5W
Energy required;
The work done here is also the energy required;
Energy required = 2646J
The energy required is 2646 J and the jogger's power output 661.5 W.
Given here,
Mass of Jogger = 60 kg
Time = 4s
Vertical height = 4.5 m
The power output of the jogger is defined as the rate of energy tranfer work is done.
Power = W/t
Where,
W- work = mgh = 60 kg x 9.8 m/s² x 4.5 m = 2646 J
t - time - 4 s
Put the values, we get
Power = 661.5W
To know more about power,
https://brainly.com/question/8288959
which of the following is true of phototsythesis but not of cellular respiration.
A- Photosynthesis releases oxygen gas as a product
B- Photosynthesis occurs in all organisms
C- Photo synthesis is a process in which glucose i broken down
D- Photosynthesis requires glucose as a reactant
Answer:
B. Photosynthesis occurs in all organisms
Hope this helps!! :)
Need help fast it’s on forces!
i think the answer is h if am wrong am sorry
Explanation:
one newton equals 0.225