Question

1. Suppose you are driving a 500-kg Zamboni when it suddenly breaks down, forcing you to get out and push. You apply a force of 85 N on the machine, which experiences a constant frictional force of 5 N. How long (in seconds) will it take to push the Zamboni the remaining 40 m?

2. The coefficient of static friction between Kylo Ren's shoes and the floor of Starkiller Base is 0.21. How large (in Newtons) is the frictional force acting on his 90 kg body when he stands on an incline that forms an angle of 20^owith the horizontal?

3. A 4 kg box is placed on a ramp that forms an angle of 26^o with the horizontal. The coefficient of friction between the ramp and the box is 0.25. How long will it take the box to slide (from rest) 18 m to the bottom of the ramp?

4.

The Atwood machine is a simple device in which an object is suspended over a pulley and attached to another as shown:

Find the acceleration of block m₁ in m/s², assuming it has a mass of 9 kg and m₂ has a mass of 6 kg (ignore the mass of the pulley and friction in the axel).

5. While camping, you decide it is imperative to protect your beef jerky from those jerk raccoons that have been following you for miles. You suspend your cooler in the air, using two ropes tied to trees as shown:

Assuming =20^o and =35^o, find the tension in the rope on the left (in Newtons).

6. A tugboat traveling through Venice is pulling two smaller boats behind it using tow cables. The tugboat is connected to boat A, which has a mass of 300 kg and experiences a constant drag force of 70 N from the water. Boat A is connected via tow cable to boat B, which has a mass of 400 kg and experiences a drag force of 85 N. The tension in the cable between the tugboat and boat A is 2800 N. Find the acceleration of boat b (in m/s²).

7. A turtle is pushing a 2.5 kg rock across a flat surface through the desert. The turtle is applying a force of 10 N on the rock, which moves at a constant velocity. How much frictional force does the rock experience (in Newtons)?

8.

Consider the configuration shown below:

in which M₁ is being pulled up a ramp by M₂, which is descending due to the force of gravity. M₁ is experiencing a constant frictional force, which causes it to move at a constant velocity. If ,M₁ = 16 kg, and M₂ = 12 kg, what is the coefficient of friction between the block and the ramp? (ignore the mass of the pulley)

Answer 1

1) F = force applied = 85 N

f = friction force = f = 5 N

m = mass = 500 kg

d = distance moved = 40 m

a = acceleration = Net force / mass = (85-5)/500 = 0.16 m/s/s.

time taken to cover 40 m is t.

using kinematic equation :

[answer]

2) component of weight on the body down the inclined plane =

the maximum friction force that can act is f = .

therefore, the frcition force that acts on the object is 174.23 N [answer]

3) The component of weight that acts on object down the inlcined palne =

friction force that acts on the object up the inclined plane is

acceleration of object = a:

17.20 - 8.82 = ma

=> a = (17.20 - 8.82)/4 = 2.095 m/s/s.

the object slides down 18 m.

using kinematic equation :

[answer]