Work
Find the weight of a 10 kg box.
98.1 N
What is the SI unit of weight?
Newtons
How much gravitational potential energy does a 12 kg rock have if it is 4 m above the ground?
471 J
The ____________ is the SI unit of power.
watt
What must occur for work to be done?
Motion must occur in the direction of the force.
True/False: A joule equals 1 Newton-second.
False, a joule equals 1 Newton-meter.
Find the kinetic energy of a 200 gram rock moving at 3 m/s.
0.9 J
How much power is consumed when Sally does 42 J of work in 2 seconds?
21 W
How much work does it take to carry a 10 kg box forward at a constant velocity of 2 m/s?
0 J
Find the mass of a 160 N heavy object.
16.3 kg
At what altitude is a 120,000 kg airplane flying if it has 7,063,200 kJ of gravitational potential energy?
6000 m
How long does it take a 200 W motor to do 700 J of work?
3.5 s
How much work does it take to lift a 10 kg box a distance of 120 cm?
118 J
What does a joule equal in SI base units?
kg * m2/s2
How fast is a 30 kg object moving if it has 1800 J of kinetic energy?
10.95 m/s
Find the power (in kilowatts) of a motor that does 25 kN of work in 3 seconds.
8.3 kN
A force moving an object right does 50 J of work. Does the same force moving an object to the left do -50 J of work?
No. Work and energy are scalars, and their sign does not change with displacement.
What does a watt equal in base SI units?
kg * m2/s3
Find the weight of a box moving at 12 m/s with a kinetic energy of 4404 J?
600 N
Jake lifts a 3 kg stone 24 cm. If this takes 2.8 seconds, how much power did it require?
2.5 W [Solution picture in Classroom]