Question 1
A hunk of cast concrete with a weight of 10 N will float if
it displaces 11 N of water.
True/false
Question 2
The density of a solid ball with a mass of 231 g and a
volume of 110 cm^3 is ____ g/cm^3
1.182
25,410
2.10
0.476
Question 3
If the distance from the Sun varied during an asteroid’s
orbit, would its kinetic energy change? Would its potential energy change?
Would the total energy (sum of kinetic and potential energy) of the asteroid
change?
kinetic energy changes, potential energy does not change,
and total energy changes
energy does not change
kinetic energy does not change, potential energy changes,
and total energy changes
kinetic energy changes, potential energy changes, and total
energy changes
Question 4
The “law of conservation of energy” is part of a
government regulated policy on energy usage.
True/false
Question 5
Work is equal to _____ .
the change in kinetic energy of an object
force multiplied by the distance an object has moved
both answers above
none of the answers above
Question 6
Power is _____ .
typically measured in kW • hr
both answers above
none of the answers above
Question 7
Evaluate (1.70×10^8)(5.900×10^-16). Be sure to follow the
guidelines for entering answers in scientific notation.
Report your answer to 2 decimal places using scientific
notation in the textboxes below.
Only one number should be to the left of the decimal point!
n.nn x 10^n
Question 8
A 1,500 kg car moving at 7.0 m/s is stopped by the action of
its brakes. The work done by the car’s brakes is ____ Joules.
Only enter your numerical answer below – do not include
units. Report your answer to 2 decimal places.
Question 9
The total energy of a 6.0 kg falling rock is 5000 J. If its
potential energy is 2,150 J, the kinetic energy of the rock is ____ J.
Only enter your numerical answer below – do not include
units.
Question 10
If the kinetic energy of a 3.4 kg falling rock is 3,120 J,
the rock’s speed is ____ m/s.
Only enter your numerical answer below – do not include
units. Report your answer to 2 decimal places.
Question 11
Assume an asteroid is in the shape of a sphere and has a
mass of 1,200 kilograms. Determine the density (in grams per cubic centimeter)
of this asteroid if its diameter is known to be 0.9 meters.
Useful information: 1 kg = 1000 g, 1 m = 100 cm, volume of
sphere = 4/3 ? r3. Remember that the radius of a sphere is equal to half its
diameter!
Only enter your numerical answer below – do not include
units. Report your answer to 2 decimal places.





