Physics Sec 3

An object of mass 50 Kg accelerates from a velocity of 2 m/s to the velocity of 10 m/s in the same direction. what is the impulse provided to cause this acceleration?

• 250 Ns

• 400 Ns

• 850 Ns

• 2500 Ns

Which quantity is measured in Newton Second (Ns)?

• Impulse

• Moment

• Power

• Workdone

The diagram shows an object of weight W and an object of weight Z balanced in a uniform meter rule. Choose the correct answer.

• A

• B

• C

• D

The diagram show four objects A,B, C and D. The centre of mass M of each object is marked on the diagrams.

Which object is not in equilibrium?

• A

• B

• C

• D

Passengers are not allowed to stand on the upper deck of double decker buses. Why?

• They would cause the bus to become less stable.

• They would cause the bus to slow down.

• They would increase the kinetic energy of the bus.

• They would lower the centre of mass of the bus.

A skier walks from the bottom of a ski slope to the top and gains 10000 j of gravitational potential energy. She skis down the slope. At the bottom of the slope, her kinetic energy is 2000 J. How much energy is dissipated in overcoming friction and air resistance as the skier moves down the slope?

• 2000 J

• 8000 J

• 10000 J

• 12 000J

Which energy source is one that is used to boil water to make steam in power station?

• energy from tides

• energy from waves

• hydroelectric energy

• nuclear energy

Which quantities are measured in the same unit?

• energy, power and work

• energy and power but not work

• energy and work but not power

• power and work but not energy

Which is a non renewal energy resource?

• Coal

• Solar

• Tides

• Wind

Which source of energy involves the splitting of heavy atoms?

• Chemical energy

• geothermal energy

• hydroelectrical energy

• nuclear energy