Physics

Question 1

normal force

Answer 1

the force or the component of a force which a surface exerts
on an object it is in contact with, and which is perpendicular to the surface

Question 2

frictional force

Answer 2

the force that opposes the motion of an object and which
acts parallel to the surface

Question 3

static frictional force

Answer 3

the force that opposes the tendency of motion of a stationary object relative to a surface

Question 4

kinetic frictional force

Answer 4

the force that opposes the motion of a moving object relative to a surface

Question 5

Newton’s first law of motion

Answer 5

A body will remain in its state of rest or motion at constant velocity unless a non-zero resultant/net force acts on it

Question 6

Newton’s second law of motion

Answer 6

When a net force acts on an object, the object will accelerate in the direction of the force and the acceleration is directly proportional to the force and inversely proportional to the mass of the object

Question 7

State Newton’s third law of motion

Answer 7

When object A exerts a force on object B, object B simultaneously exerts an oppositely directed force of equal magnitude on object A

Question 8

Newton’s Law of Universal Gravitation

Answer 8

Each body in the universe attracts every other body with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers

Question 9

weight

Answer 9

the gravitational force the Earth exerts on any object on or near its surface

Question 10

momentum

Answer 10

the product of an objects mass and its velocity

Question 11

linear momentum

Answer 11

a vector quantity with the same direction of the velocity of the object

Question 12

Newton’s Second Law in terms of momentum

Answer 12

The net force acting on an object is equal to the rate of change of momentum of the object in the direction of the net force

Question 13

impulse

Answer 13

the product of the net force acting on an object and the time it takes the net force to act on an object

Question 14

the principle of conservation of linear momentum

Answer 14

The total linear momentum of an isolated system is conserved

Question 15

projectile

Answer 15

an object which has been given an initial velocity and then it moves under the influence of the gravitational force only

Question 16

free fall

Answer 16

motion during which the only force acting on an object is the gravitational force

Question 17

work done on an object by a constant force

Answer 17

the product of the magnitude of the force, the magnitude of the displacement, and the angle between the force and the displacement

Question 18

Work-energy theorem

Answer 18

The work done on an object by a net force is equal to the change in an object’s kinetic energy

Question 18

conservative force

Answer 18

a force for which the work done in moving an object between two points is independent of the path taken. gravitational force, the elastic force in a spring and electrostatic forces

Question 19

non-conservative force

Answer 19

a force for which the work done in moving an object between two points depends on the path taken. frictional force, air resistance, tension in a chord

Question 20

the principle of conservation of mechanical energy

Answer 20

The total mechanical energy in an isolated system remains constant

Question 21

power

Answer 21

the rate at which work is done or energy is expended

Question 22

The doppler effect

Answer 22

the change in frequency/pitch of the sound detected by the listener, because the sound source and the listener have different velocities relative to the medium of sound propagation

Question 23

Coloumb’s Law

Answer 23

the magnitude of the electrostatic force exerted by one point charge on another point charge is directly proportional to the product of the magnitude of the charges and inversely proportional to the square of the distance between them

Question 24

electric field

Answer 24

a region of space in which an electric charge experiences a force. The direction of the field at that point is the direction that a positive test charge would move if placed at that point

Question 25

electric field at a point

Answer 25

the electrostatic force experienced per unit positive charge placed at that point

Question 26

Ohm’s law

Answer 26

The potential difference across a conductor is directly proportional to the current in the conductor at a constant temperature

Question 27

EMF

Answer 27

the maximum energy provided by a battery per unit charge passing through it

Question 28

rms potential difference

Answer 28

The AC potential difference which dissipates/produces the same amount of energy as an equivalent DC potential difference

Question 29

rms current

Answer 29

The alternating current which dissipates/produces the same amount of energy as an equivalent direct current

Question 30

photoelectric effect

Answer 30

the process whereby electrons are ejected from a metal surface when light of a suitable frequency is incident on that surface

Question 31

threshold frequency

Answer 31

the minimum frequency of light needed to emit electrons from a certain metal surface

Question 32

work function

Answer 32

the minimum energy that an electron in the metal needs to be emitted from the metal surface