Answer:
true
Explanation:
Friction occurs because no surface is perfectly smooth. Rougher surfaces have more friction between them. Heavier objects also have more friction because they press together with greater force. Friction produces heat because it causes the molecules on rubbing surfaces to move faster and have more energy.
Answer:
F = 69.5 [N]
Explanation:
We must remember that the friction force is defined as the product of the normal force by the coefficient of friction, and it can be calculated by the following expression.

where:
N = normal force [N]
miu = friction coefficient
f = friction force = 22 [N]
Now we must calculate the force exerted by means of Newton's second law which tells us that the sum of forces on a body is equal to the product of mass by acceleration.

where:
F = force exerted [N]
f = friction force [N]
m = mass = 95 [kg]
a = acceleration = 0.5 [m/s²]
Now replacing:
![F - 22 = 95*0.5\\F = 47.5 + 22\\F = 69.5 [N]](https://tex.z-dn.net/?f=F%20-%2022%20%3D%2095%2A0.5%5C%5CF%20%3D%2047.5%20%2B%2022%5C%5CF%20%3D%2069.5%20%5BN%5D)
5.4*10^-19 C
Explanation:
For the purposes of this question, charges essentially come in packages that are the size of an electron (or proton since they have the same magnitude of charge). The charge on an electron is -1.6*10^-19
Therefore, any object should have a charge that is a multiple of the charge of an electron - It would not make sense to have a charge equivalent to 1.5 electrons since you can't exactly split the electron in half. So the charge of any integer number of electrons can be transferred to another object.
Charge = q(electron)*n(#electrons)
Since 5.4/1.6 = 3.375, we know that it can not be the right answer because the answer is not an integer.
If you divide every other option listed by the charge of an electron, you will get an integer number.
(16*10^-19 C)/(1.6*10^-19C) = 10
(-6.4*10^-19 C)/(1.6*10^-19C) = -4
(4.8*10^-19 C)/(1.6*10^-19C) = 3
(5.4*10^-19 C)/(1.6*10^-19C) = 3.375
(3.2*10^-19C)/(1.6*10^-19C) = 2
etc.
I hope this helps!
Answer:
d. It is equal to the component of the gravitational force acting down the ramp.
Explanation:
The stationary crate is inclined at an angle with the horizontal. The Recall, Frictional Force is any Force that opposes motion.
Because the Force of Friction that is opposing the motion of the crate along the inclination side.
Therefore this Frictional force is balanced or equal to the force that is driving the inclined force.
Hence Frictional Force is equal to the Gravitational Force that is acting in the ramp, that is why the crate is stationery.