9L: Pressure and Moments

Pressure =
1. force/area
2. force x area
3. area x force
4. area/force
Which of the following is not a unit of pressure?
1. N
2. N/cm2
3. Pa
4. N/m2
Which of the following shoes would exert the least pressure?
1. Snow shoes
2. Trainers
3. High heels
4. Wellington boots
A man weighs 600N and the area of both his shoes is 150 cm2. What is the pressure on the ground?
1. 4 N/cm2
2. 750 N/cm2
3. 3 N/cm2
4. 0.4 N/cm2
We can use the pressure of liquids to work machines. This is called
1. hydraulics
2. pneumatics
3. mechanics
4. molecules
A lever which turns a small movement near the centre to a large movement at the outside is called
1. distance magnifier
2. force magnifier
3. movement maker
4. distance increaser
A lever which makes a small force able to lift a large load is called a
1. force magnifier
2. load magnifier
3. distance magnifier
4. load lifter
A system of ……………can be used to make lifting loads easier
1. pulleys
2. stairs
3. loads
4. levers
The turning effect of a force is called a
1. moment
2. spin
3. load
4. rotation
Moment =
1. force x distance
2. force/distance
3. distance/force
4. force x rotation
A person is trying to undo the nut on a lorry wheel. Which length of spanner will make life easiest?
1. 400cm
2. 40cm
3. 4cm
4. 12cm
If we apply a load of 20N to a 30cm spanner what will the turning force be?
1. 6 Nm
2. 1.5 Nm
3. 600 Nm
4. 15 Nm
In equilibrium
1. the anticlockwise moment = the clockwise moment
2. the anticlockwise moment > than the clockwise moment
3. the anticlockwise moment < than the clockwise moment
4. there is only a clockwise moment
A long spanner is
1. easier to use than a short spanner
2. harder to use than a short spanner
3. just the same as using a short spanner
4. only harder to use if the nut is wet
Weight is a force, it is caused by
1. the pull of gravity
2. the size of an object
3. the resistance of the air
4. how streamlined an object is
Which of the following will create the least pressure
1. camels foot
2. point of a drawing pin
3. edge of a knife
4. pastry cutter
Which of the following is a unit of area?
1. square metres
2. cm cubed
3. ml
4. mph
Air pressure is caused by
1. the collisions of millions of tiny molecules with the surface of an object
2. the air trying to push the surface down
3. the molecules of air trying to attract each other
4. the molecules of air reacting with the surface of an object
Levers and pulleys are both simple
1. machines
2. ideas
3. forces
4. types of energy transfers
When trying to close a door it will be easier if you
1. push on the edge furthest away from the hinges
2. push on the edge closest to the hinges
3. push in the middle of the door
4. push along the bottom of the door in the middle
Energy that is transferred into a from that is not useful is called
1. wasted energy
2. heat energy
3. light energy
4. destroyed energy
If an object is stable then it will have
1. a low centre of gravity
2. a large mass
3. a small base
4. a large span
We can balance a crane lifting a load using a
1. counter-weight
2. counter top
3. back weight
4. a top pan balance
When we pump up a bicycle tyre the friction caused by the air molecules rubbing against the tyre valve causes
1. heat to build up
2. limescale to build up
3. the tyre to wobble
4. the wheel to bend
We can use the pressure of gases to work machines. This is called
1. pneumatics
2. hydraulics
3. mechanics
4. molecules
Which of these is a unit of volume
1. cm3
2. m2
3. mph
4. J
Which of the following wheel barrows will be the best on soft ground?
1. Large, wide tyre pumped up but not too hard
2. Very hard tyre with a small area
3. Small solid rubber wheel
4. Large, narrow soid rubber wheel
A large force pressing on a small area gives
1. a high pressure
2. a low pressure
3. a greater resistance
4. a small resistance
Energy cannot be created nor destroyed, it can only be ……………………from one form into another
1. transferred
2. transported
3. transposed
4. transcended