Physics I

Additional Problems                   Do all work on a separate sheet of paper !!!

Newton’s Laws  2 points each

 

 

1.                 How much tension force (FT) must a rope withstand if it is used to accelerate a

1700 kg car at a rate of .5 m/s/s ??

 

2.                 The “push-off” period when a flea jumps lasts about 1.0 x 10-3 seconds, during

which time the flea’s legs push against the ground and accelerate the flea to a speed of 1.0 m/s.  Consider the mass of the flea to be 5.0 x 10–7 kg.  Calculate the force applied by the flea against the ground.

 

3.                 A net force of 26.4 N accelerates an object at 10.8 m/s/s.  What is the mass of the

object ??

 

4.                 How much force is needed to accelerate a 6.0 gram bullet from rest to 500 m/s

over a distance of .70 meters ??

 

5.                 A person has a reasonable chance of surviving an automobile crash if the

deceleration does not exceed 30 g’s (30 times the acceleration of gravity).  Calculate the force on a 65 kg person accelerating at this rate.

 

6.                 What is the force exerted on a 7.0 kg shot by a shot-putter if the shot is moved

through a distance of 1.7 meters and is released with a speed of 14.0 m/s ??

 

7.                 A .10 gram spider is descending on a strand that supports the spider with a tension

force (FT) of 5.6 x 10 –4 N.  Ignoring things like air resistance, friction, etc., what would be the acceleration of the spider ??

 

 

 

Extra Credit: (10 pts)

8.       An exceptional standing jump would raise a person .80 meters off the ground.  To

do this, what force must a 70 kg person exert against the ground ??  (Assume that the person must first lower himself .2 meters in order to accelerate for the jump.)