Legend

 Fnet = net force m = mass a = acceleration Fg = force of gravity Ff = force of friction

Problems

 Before you start the Problems, be sure to have a pen/pencil and paper for working out the problems, and also a calculator.  If you want to use our java calculator:

1) An object is sliding down a frictionless incline; the object has:
a) constant speed
b) constant velocity
c) constant acceleration
d) changing acceleration
Simply type the letter in the box like "x", without quotes.

2) The following frictionless system accelerates at 1.60 m/s2 when released.

What is the tension in the string during acceleration?

 N

3)  Force F gives mass m1 an acceleration of 4.0 m/s2.  The same force F gives m2 an acceleration of 2.0 m/s2.  What acceleration would force F give to the two masses m1 and m2 if they were glued together?

 m/s2

4) The 4.0 kg block accelerates across a frictionless table at 1.5 m/s2. n Find the mass of m1.

 kg

5)  A cyclist traveling at 10 m/s applies her brakes and stops in 25 m.  The graph shows the magnitude of the braking force versus the distance traveled.

What is the total mass of the bike and cyclist?

 kg

6)  A 65.0 kg   block is being accelerated along a level surface.  The applied force is 500 N and the friction force is 300 N.  What is the coefficient of friction between the block and the surface?

7)  A  75 kg man stands on a scale while accelerating upwards in an elevator.  If the scale reads 850 N, what is the magnitude of the acceleration of the elevator?

 m/s2

8)  A person pushes a 16 kg lawnmower at constant speed with a force of 80 N directed along the handle, which is at an angle of 45o to the horizontal.

a) what is the horizontal force of the lawnmower?
b) what is the normal force exerted vertically upward on the mower by the ground?
c) What is the force required to accelerate it from rest to 1.5 m/s in 2.5 seconds?

 N
 N
 N
 RESULTS

1) constant acceleration
2) 16.4 N
3) 1.3 m/s2

4) 0.72 kg
5) 64 kg
6) 0.47
7) 1.5 m/s2
8) a. 57 N b. 210 N c. 94 N
 Formulas Work & Energy