Test - Unit 5 Energy

Question 1

43. What is the mass of a squirrel if it has 40 J of potential energy and is sitting on a house 2.5 m tall?

Answer 1

m= 1.633 kg (decimal was in wrong place)

Question 2

44. An 8 kg toddler is running and using 400 J of kinetic energy. What is the velocity of the child?

Answer 2

v= 10 m/s forwards (forgot direction)

Question 3

48. A recycling center is melting down gold. It starts out at 18 degrees C and reaches its melting point at 108 degrees C by absorbing 153,000 J of energy. What was the mass of he melted gold? Note: gold has a specific heat of 136 J/kg/C.

Answer 3

Q= 153,000
c= 136
(were in wrong place)
m= 1,125 kg

Question 4

52. A piece of zinc was lying outside and has a temperature of 26 degrees C. Later that day the sun came out and the heat increased to 36 degrees C. If the piece of zinc is only 0.15 kg, find he thermal energy. Note: zinc had a specific heat of 380 J/kg/C.

Answer 4

Q= 380 J/kg/C

forgot to put down on find

Question 5

Which pictures show the same type of thermal energy transfer?

Answer 5

A and C

both show conduction, ex: a frying pan, pot of boiling water

Question 6

As the time required to do a given amount of work decreases, the power developed…

Answer 6

increases