Force Direction / Pulleys

Front

A load of 100 newtons is lifted with this pulley setup. Assuming no friction, how much force is needed to do the lifting?

Back

50

Answer explanation

Two supporting strands will produce twice as much lifting force so in this situation you need half as much applied force.

The trade off is that you need to pull twice as far.

Front

An effort of 200 newtons is applied to this pulley setup. How many newtons of lifting force will it produce?

Back

400

Answer explanation

Two supporting strands will produce twice the amount of force applied to it.

The tradeoff is that you have to pull twice as far.

Front

A load of 100 newtons is lifted with this pulley setup. Assuming no friction, how much force is needed to do the lifting?

Back

50

Answer explanation

Two supporting strands will produce twice as much lifting force so in this situation you need half as much applied force.

The trade off is that you need to pull twice as far.

Front

An effort of 200 newtons is applied to this pulley setup. How many newtons of lifting force will it produce?

Back

400

Answer explanation

Two supporting strands will produce twice the amount of force applied to it.

The tradeoff is that you have to pull twice as far.

Front

An effort of 100 newtons is applied to this pulley setup. How many newtons of lifting force will it produce? (Ignore the 300 kg in the picture)

Back

600 N

Answer explanation

Six supporting strands will produce six times the amount of force applied to it.

The tradeoff is that you have to pull six times as far.

Front

A load of 600 newtons is lifted with this pulley setup. Assuming no friction, how much force is needed to do the lifting?

Back

100 N

Answer explanation

Six supporting strands will produce six times as much lifting force so in this situation you 1/6 as much applied force.

The trade off is that you need to pull six times as far.

Front

A load of 30 newtons is lifted with this pulley setup. Assuming no friction, how much force is needed to do the lifting?

Back

30 N

Answer explanation

There is only one supporting strand so the pulley does not change the amount of force needed to lift the object. It does allow a downward pull to produce an upward lifting force.

Front

The arrows show the direction of a pushing force. Which arrow shows the pushing direction that will require the least amount of force to move the car?

Back

Arrow C

Answer explanation

Arrow C is point the most in the direction that you want the car to move so that will require the least amount of force.

Front

A backpack is hung to keep it away from bears. Which arrangement would require the least tension (force) in the rope? Arrangement X, Arrangement Y, Arrangement Z, They are all the same because they all have the same backpack.

Back

Arrangement X

Answer explanation

To hold the backpack up, an upward force is needed. Arrangement X has the ropes pulling more in the upward direction (which wastes the least force going sideways) so it requires the least amount of force.

Front

A backpack is hung to keep it away from bears. Which arrangement would require the strongest rope? Arrangement X, Arrangement Y, Arrangement Z, They are all the same because they all have the same backpack.

Back

Arrangement Z

Answer explanation

To hold the backpack up, an upward force is needed. Arrangement Z has the ropes pulling mostly sideways which wastes the most force and will result in the most force along the ropes.