1) a 100. N Box Is at Rest on a Tabletop Where the Coefficients of Friction Are 0.400 Static

Forces Worksheet

1) A 100. N box is at rest on a tabletop where the coefficients of friction are 0.400 static and 0.300 kinetic. a) What force of friction will be present if you push on it horizontally westward with 35.0 N? b) Give magnitude and direction of friction force.

2) A 30.0 kg crate is at rest on a factory floor. a) If the coefficients of friction are 0.300 static and 0.100 kinetic, what force will it take to get the crate moving? b) Once moving, how much force will it take to keep it moving at a constant speed?

3) A large 50.0 kg crate is at rest on level ground. Two people push on the crate. One pushes north with 200. N while the other pushes South with 50.0 N. a) If there is no friction, draw a diagram of this object labeling all forces with names and values. b) Find the acceleration and direction of acceleration for the crate.

4) A 500. N boy is standing on frictionless roller skates. If someone pulls him, horizontally, with 40.0 N of force to the North, what will be his acceleration?

5) A big 100. kg box is rolling on frictionless wheels, to the West at 4.00 m/s. If you need to stop it in 2.00 seconds, what force will this require (direction too)?

6) An 80.0 kg basketball player jumps, by accelerating herself upwards at 16.0 m/s2. What force does her shoes exert on the ground during this acceleration? How long is her hang-time if her V0 is 4.00 m/s? (how long in the air)

7) Find the acceleration of the following pair of connected objects.

10 kg 8) A 1000. kg car accelerates from 0 to 30.0 m/ s in 10.0 seconds. What unbalanced force must the engine of the car produce?

9) A force of 15.0 N is applied to an object with a mass of 5.00 kg. What will be the object's final velocity after 10.0 seconds?

10) A 20.0 kg crate of physics books is at rest on a table. What is the normal force on the books?

11) You pull horizontally on a 300. N sled packed with presents, which is initially at rest. a) If the coefficients of friction are 0.4 Static and 0.3 Kinetic will you be able to move it if you pull with 100. N? Why or why not? b) How would this change if the sled were already sliding?

12) A rocket of mass 10000. kg on the surface of the earth accelerates upward at a rate of 4.00 m/s2. What is the force provided by the rocket engines?

13) What is the value of gravity where a pendulum 1.08 m long has a period of 2.05 s?

15) A trapeze artist swings in simple harmonic motion with a period of 3.80 s. Calculate the length of the cables supporting the trapeze.

16) A mass of .300 kg is attached to a spring and is set into vibration with a period of .240 s. What is the spring constant of the spring?

17) A spring of spring constant 30.0 N/m is attached to a 2.30 kg mass, and the system is set in motion. Find the period and frequency of vibration for this spring.