The moment of a force causes an object to

• move forward

• move backward

• stop moving

• turn about a fixed point

The turning effect of a force on a door is greater when it is applied at

• A point near the hinges and perpendicular to the door

• A point near the hinges and parallel to the door

• A point far away from the hinges and perpendicular to the door

• A point far away from the hinges and parallel to the door

The diagram shows a light beam pivoted at one end. What is the effort required to lift the load?

• 50

• 67

• 100

• 200

Jack has a weight of 300 N and sits 2.0 m from the pivot of see-saw. Jill has a weight of 450 N and sits 1.5 m from pivot. Who will move down?

• Jack

• Jill

• Both of them

• None of them

Tags

NGSS.MS-PS2-4

The diagram shows the first step in an experiment to determine the position of the centre of mass of a thin card.

What is the next step in this experiment?

• Find the mid-point of PQ.

• Hang the card from point R.

• Measure the mass of the card.

• Measure the thickness of the card.

Diagram shows an object of weight W and an object of weight Z balanced on a uniform metre rule.

Which equation relating to W, Z, a and b is correct?

• W/a = Z/b

• W × Z = a × b

• W × a = Z × b

• W × (a + b) = Z

A uniform bar of length 1.0 m is supported 30 cm from one end. In order to balance the bar, a weight of 10 N is glued on the end.

What is the weight of the bar? (Leave ans in 3s.f)

A pupil balances a non-uniform object on a knife edge. To do this, a weight is suspended from the left-hand end of the object.

AWhere is the centre of gravity of the object?

• A

• B

• C

• D

The figure shows a stool. A horizontal force F keeps the stool balanced. C is the centre of gravity of the stool and the weight of the stool is 30 N.

At which point will the normal contact force be acting?

Little Jack uses a metal rod to raise a large stone, as shown below.

Which force would raise the large stone most easily?

• A

• B

• C

• D