Work Energy Problems review for test

1. How much work is required to push a 5 kg object with a force of 40 n horizontally for a distance of 3 m?

Data                 Principle                       Formula                                    Solution            Answer

           

                                   

 

                                                                                                      120 J

 

2. Same problem as above with the force applied at an angle of 30 degrees with respect to the force.  Draw a figure!

Data                 Principle                       Formula                                    Solution            Answer

 

 

 

                                                                                                                        104J

 

3. How much work is required to raise the 5 kg object 3m vertically?

Data                 Principle                       Formula                                    Solution            Answer

 

 

 

 

                                                                                                                                    147J

 

4. How much work is required to push the 5 kg object up a frictionless plane that is at 30 degrees with the horizontal if the final vertical height obtained is 3m?

Data                 Principle                       Formula                                    Solution            Answer

 

 

 

 

                                                                                                                                    147J                                                                                                                            

 

5. A 3 kg hammer moving 10 m/s hits a nail and drives it 2 cm.  What was the force on the nail?

Principle:                      Formula                        Work                           Answer

 

Data

 

 

 

                                                                                                                                    7500N

6. How fast will a 5 kg rocket be traveling if its motor has a force of 2000 n and it operates for 500 m?

Principle:                      Formula                        Work                           Answer

 

Data

                                                                                                                                    632 m/s

 

7. A ball is thrown straight into the air with a velocity of 30 m/s.  How high does it rise?

Principle:                      Formula                        Work                           Answer

 

Data                                                                                                                             45.9 m

 

 

 

8. A boy falls off a 2 m high pier into a lake.  How fast is he moving when he hits the water? Principle:                Formula                        Work                           Answer

 

Data                                                                                                                        6.23 m/s

 

 

 

9. A 30 kg girl falls head first off a 1.5 m ladder and her head makes an impression in the ground that is 5 cm deep.  What was the average force of the ground on her head?

Principle:                      Formula                        Work                           Answer

 

Data                                                                                                                         8820 n

 

 

 

 

10. A 1 kg weight falls 2 m and hits a stick with a force of 1000 N.  How far will the stick be driven into the ground?

Principle:                      Formula                        Work                           Answer

 

Data                                                                                                                      2 cm

 

 

 

11. A 1000 kg truck traveling 20 m/s hit a parked car with a force of 20,000 N.  How far does it push the car?

Principle:                      Formula                        Work                           Answer

 

Data                                                                                                                         10 m

 

 

 

 

 

 

 

12.  A 1000 kg car rolls down a 10 m high hill without friction starting from a stop.  How fast is it traveling at the bottom of the hill?

Principle           Data                             Formula                                    Solution            Answer

 

 

 

                                                                                                                                    14 m/s

13. How much work is required to raise a 10 kg object 30 m?    Give the Total Energy, the Potential energy and the Kinetic Energy at that point.    (At rest 30 m above the ground)

Data                             Formula                                    Solution                        Answer

 

Work                                                                                                                      _______ (2940 J)

P.E                                                                                                                          _______(2940 J)

K.E.                                                                                                                        _______(0)

Total Energy:                                                                                                           _______(2940 J)

 

When the 10 kg object has fallen 10 m, give the potential energy, the kinetic energy, and the total energy of the object.

Data                             Formula                                    Solution                        Answer

 

P.E                                                                                                                   _______1960J

 

K.E.                                                                                                              _______980 J

 

Total Energy:                                                                                                    _______(2940 J)

 

Give the total energy, the potential energy, and the kinetic energy of the object just before it strikes the ground. (It is at ground level still moving full speed.)

Data                             Formula                                    Solution                        Answer

 

P.E                                                                                                                   _______(0)

K.E.                                                                                                                 _______(2940 J)

Total Energy:                                                                                                    _______(2940 J)

 

14. What is the amount of heat energy released when the 10 kg object hits the ground?

Data                             Formula                                    Solution                        Answer

 

                                                                                                            _______(2940 J)