Physics 1/26/22

The sum of the kinetic and potential energy in a system is known as the system's _____________________ energy.

• mechanical

• chemical

• thermal

• combined

A spring with spring constant 4 N/m is compressed by 0.25 m. How much energy is stored in the spring?

• 1 J
• 0.25 J
• 0.125 J
• 16 J

What form of energy does our bungee jumper have when they are hanging from the cord at the bottom of the jump?

• Kinetic

• Gravitational Potential

• Elastic Potential

• Sound

An object is speeding up when: (Choose All That Apply) (May have to choose more than 1 to be right)

• it is gaining kinetic energy.

• it is losing kinetic energy.

• it is gaining gravitational potential energy.

• it is losing gravitational potential energy.

At point C, the mass in the pendulum has ________ PE, and ________ KE.

• maximum, maximum

• maximum, minimum

• minimum, maximum

• not sure

At point A and E, the mass in the pendulum has ________ PE, and ________ KE.

• maximum, maximum

• maximum, minimum

• minimum, maximum

• not sure

At every point the mechanical energy...

• is constant

• is zero

• is changing

A spring with k=73 N/m is compressed 70 cm.  An object of mass 4 kg is attached to one end of the compressed spring.  What is the acceleration of the object at the moment the spring is released?  

• .078 m/s/s
• 0.17 m/s/s
• 13 m/s/s
• 1.3 X 10^5 m/s/s

A force of 470 N is applied to stretch a spring which has a spring constant, k=1100 N/m.  How much does the spring stretch past its free length?

• 0.214 m
• 2.34 m
• 0.427 m
• 5.17 X 10^5 m

Which of the following springs is the stiffest?

• A spring that requires a froce of 2000 N to compress it by 6.8 m.
• A spring that requires a force of 4000 N to stretch it by 9.0 m. 
• A spring that requires a force of 8000 N to compress it by 45 m.  
• A spring that requires a force of 4800 N to stretch it by 14 m.