Work
Power
Energy
Misc
Audience Choice
100
Work is _________ acting upon an object to cause displacement.
force
100
What is the formula for power?
power = w/t
power = force x velocity
100
An object in motion has _________ energy.
kinetic
100
A 5 kg ball is 100 m above the ground. A 10 kg ball is 50 m above the ground. Which has more potential energy?
same PE
100
KE plus PE = ________
mechanical energy
ME
200
If no displacement happens, then no __________ happens.
work
200
What is the unit for power?
watt
200
What is the formula for potential energy?
PE = m x g x h
mass x gravity x height
200
A bicycle has a kinetic energy of 100 Joules.
What kinetic energy would the bicycle have if it had the same mass and was moving with twice the speed?
400 J
200
Energy can be lost in a closed system.
True or False
False
energy is conserved in a closed system
300
A book falls off a table and onto the ground. Is this work?
(answer Yes or No)
yes
300
Bob and Alice ran up a hill. Bob is twice as massive as Alice; yet Alice ascends the same distance in half the time. Who did the most work?
Bob
Bob must apply twice the force to lift his twice-as-massive body up the same hill
300
The sum of PE and KE is _________?
mechanical energy
300
Kinetic energy is a vector quantity.
True or False?
false
it is scalar
300
If 150 J of work is needed to move a box 10 m, what force was used?
A. 1500 N
B. 15 N
C. 1.5 N
D. 150 N
B. 15 N
400
A waiter carries a tray full of meals above his head by one arm across the room.
Is work being done?
No
400
Bob and Alice ran up a hill. Bob is twice as massive as Alice; yet Alice ascends the same distance in half the time. Who has the most power?
they have the same amount of power
Alice does one-half the work yet does it one-half the time. The reduction in work done is compensated for by the reduction in time.
400
A bicycle has a kinetic energy of 100 Joules.
What kinetic energy would the bicycle have if it had twice the mass and was moving at the same speed?
200 J
400
A joule = 1 Newton x foot
True or False
False, it is Newton x meter
400
A car with a mass of 1000 kg is traveling at 20m/s. What is it's KE?
A. 200,000 J
B. 400,000 J
C. 500,000 J
D. 1,000,000 J
B. 400,000 J
500
The standard metric unit for work is the ______.
joule
500
Vi and Caitlyn are lifting weights. Vi lifts 10 kg dumbbells 10 times in a minute. Caitlyn lifts the same dumbbells 10 times in 10 seconds. Who has more power?
Caitlyn
Same amount of work but less time.
500
A 5 kg object is lifted to a height of 10 m. What is the potential energy of the object?
490 J
500
A 10-N force is applied to push a block across a frictional surface for a displacement of 5.0 m to the right.
Which forces cause work?
Fapp and Ffrict cause work.
Vertical forces don't cause horizontal displacement.
500
If the speed of an object is doubled, what happens to its kinetic energy?
A. remains the same
B. doubles
C. quadruples
D. halved
C. quadruples