Forces

Question 1

Contact forces?

Answer 1

Frictional force

Question 2

Non-contact forces?

Answer 2

Gravitational force

Magnetic force

Question 3

Formula for speed?

Answer 3

speed = distance / time

Question 4

Formula for pressure?

Answer 4

pressure = force / area

Question 5

S.I. Unit for Force / Weight?

Answer 5

Newton (N)

Question 6

Define weight

Answer 6

Amount of gravitational force acting on an object

Question 7

Define mass

Answer 7

Amount of matter in an object

Question 8

S.I. Unit for Mass?

Answer 8

Kilogram (kg)

Question 9

Instruments to measure weight?

Answer 9

Spring balance *
Weighing machine
Compression balance

Question 10

Instruments to measure mass?

Answer 10

Electronic balance *

Beam balance

Question 11

How to calculate weight?

Answer 11

Weight = mass × gravitational force

Question 12

Difference between mass and weight?

Answer 12

Mass - remains the same

Weight - changes as gravity changes

Question 13

Effects of a force?

Answer 13

1. Forces can change the SIZE / SHAPE of an object
2. Forces can change the MOTION of an object
3. A force applied to a MOVING object can change its DIRECTION
4. A force applied to a MOVING object can change the SPEED
5. A force applied to a MOVING object can STOP it
6. A force applied to a STATIONARY object can make it MOVE

Question 14

Example of turning effect of forces?

Answer 14

Levers - by applying a force at one point of a lever, the force at another point can be overcome

Question 15

Examples of levers?

Answer 15

1. Crowbar
2. Fishing rod
3. Wheelbarrow

Question 16

Define force

Answer 16

A push or a pull resulting from an interaction with another object