QQC CE 02

Change 0.6kg into a FORCE.

Do not include the units (N)

Answer explanation

F = Mx10 = 0.6 x10 = 6

Change 98N into a mass.

Do not include the units (kg)

Answer explanation

M = F/10 = 98/10 = 9.8

Hot air rises! This is because...

• It is hot

• Hot air is less dense

• The cold air pushes it up

• The particles are moving faster

Aluminium has a density of 2.7g/cm³. What is the volume of a 2.7kg block?

Look out for the units of the block. Do not include the units (cm³)

Answer explanation

M = 2.7 x1000 = 2700g

V = M/D =2700/2.7 = 1000

Why do you see lightning before hearing the thunder?

• light is faster than sound

• light is much faster than sound

• the thunder has to travel though the clouds

• sound is slower than light

What is the average speed of a falling balloon if it takes 5s to drop 2m?

Do not include the units (m/s)

Answer explanation

S = D/T = 2/5 = 0.4

Why do skis stop you sinking into soft snow?

• They are long

• They are lightweight

• They increase your pressure on the snow

• They spread your weight out

What is the force on a disc break if the fluid is at a pressure of 0.25 N/cm² and the discs have an area of 200cm²?

Do not include the units (N)

Answer explanation

F = PxA = 0.25x200 = 50

How can you open a heavy door more easily using moments?

• Oil the hinge

• push the door from the other side rather than pulling

• push with a bigger force

• push closer to the hinge (pivot)

The clockwise moment on a seesaw is 600Nm. What would the weight of a person be if they were sat 1.5m out and it balances?

Do not include the units (N)

Answer explanation

F = Moment / D = 600/1.5 = 400