Physics - Power

Power

Physics

Power is the rate at which energy is converted from one type to another within a system:

​There are two ways to define power:

Or, if work is being done, then power is the rate at which work is being done on the system:

Power has units of Watts

Watts = Joules / Seconds

Multiple Choice

Jason and Brent race up a hill that is 30 m high. Jason takes a path that is 60 m while Brent uses a longer path that is 100 m long. It takes Jason 40 seconds but Brent only 30 seconds. They both start from rest and stop at the top. They also have the same weight. Jason does

• more work than Brent.

• the same amount of work as Brent.

• less work than Brent.

Multiple Choice

Jason and Brent race up a hill that is 30 m high. Jason takes a path that is 60 m while Brent uses a longer path that is 100 m long. It takes Jason 40 seconds but Brent only 30 seconds. They both start from rest and stop at the top. They also have the same weight. The power generated by Jason going up the hill is

• greater than the power generated by Brent.

• equal to the power generated by Brent.

• less than the power generated by Brent.

Multiple Choice

Abbie and Bonita race up a 30 m high hill. Abbie takes a 60 meter path while Bonita takes a 100 meter path. It takes Abbie 40 seconds because her path is steeper than Bonita's, who takes only 30 seconds. Abbie's weight is 700 N; Bonita's is 500 N. They both start from rest and stop at the top. The work Abbie does going up the hill is

• less than the work Bonita does.

• same as the work Bonita does.

• greater than the work Bonita does.

Multiple Choice

Abbie and Bonita race up a 30 m high hill. Abbie takes a 60 meter path while Bonita takes a 100 meter path. It takes Abbie 40 seconds because her path is steeper than Bonita's, who takes only 30 seconds. Abbie's weight is 700 N; Bonita's is 500 N. They both start from rest and stop at the top. The power generated by Abbie going up the hill is

• less than the power generated by Bonita.

• equal to the power generated by Bonita.

• greater than the power generated by Bonita.

Poll

I find the topic of power

• pretty straightforward;

  I feel confident.

• a little confusing;

  I need more practice.

• completely awful...I don't get this at all.