Forces and Newton's Laws

1

What is the weight of a 65kg person on the Earth?

2

What is the weight of a 65kg person on the moon where g=1.6\,Nkg^{-1}?

3

What is the unbalanced force acting a on a rocket if its weight is 25,000 N and the thrust of its engines is 35,000N?

4

The cyclist and bicycle have a combined mass of 80kg and accelerate forwards at 0.9\,m\,s^{-2}. Calculate the size of the unbalanced force producing this acceleration.

Side-on view of cyclist with green arrow indicating direction of travel, right to left.

5

Two forces act on a parachutist during a drop. One force is the weight W of the parachutist. The other force is the upwards pull P from the parachute harness on the parachutist. The parachutist has a mass of 50kg. What is the acceleration of the parachutist?

Parachutist falling to earth. A green force arrow points up labelled  'P - 400 N' and a purple force arrow points down labelled 'W - 500 N'.

6

A shopping trolley and its contents have a mass of 20kg. The trolley is pushed with a force P. The friction force acting on the trolley is 15\,N. The acceleration of the trolley is 0\cdot5\,m\,s^{-2} in the forward direction. What is the size of the unbalanced force acting on the trolley?

Side-on view of shopping trolley. A green force arrow points left labelled 20 N and a purple force arrow points right labelled P.

7

A shopping trolley and its contents have a mass of 20kg. The trolley is pushed with a force P. The friction force acting on the trolley is 15N. The acceleration of the trolley is 0\cdot5\,m\,s^{-2} in the forward direction. What is the size of force P?

Side-on view of shopping trolley. A green force arrow points left labelled 20 N and a purple force arrow points right labelled P.

8

A 20N force and a 15N force act on a crate at right angles, as shown in the diagram.

Side-on view of a crate. A green force arrow points up labelled 20 N and a purple force arrow points right labelled 15 N.

What is the magnitude of the resultant force?

9

A 20N force and a 15N force act on a crate at right angles, as shown in the diagram.

Side-on view of a crate. A green force arrow points up labelled 20 N and a purple force arrow points right labelled 15 N.

What is the direction of the resultant force?