Exercises potential & kinetic energy (2nd ESO)

1.       A car with a mass of 45 kg has a speed of 45 m/s. What’s its kinetic energy?

2.       A car with a mass of 4.5 T_m has a speed of 45 km/h. What’s its kinetic energy?

3.       A car with a mass of 4500 g has a speed of 0.45 km/s. What’s its kinetic energy?

4.       A car with a mass of 450 kg has a speed of 450 m/s. What’s its kinetic energy?

5.       A spider is on top of a building with a height of 45000 mm. If the potential energy of the spider, on Earth, is 900 J. What is the mass of the spider?

6.       A billiard ball is on top of a building with a height of 500 dm. If the mass of the ball is 400 g, what is the speed of the ball when it falls down and arrives to the floor?

7.       A motorbike runs from Socuéllamos to Tomelloso. The distance among these two cities is 17 km. The mass of the motorbike and its driver is 500 kg, and the kinetic energy has a value of 25 kJ. How many seconds does it take to the motorbike to travel from Socuéllamos to Tomelloso?

8.       Transform the following units:

a.       23 m/s to km/h

b.      333 km/year to mm/s

c.       670 m/min to cm/s

d.      1000 m/year to km/century