Mechanics 1

Question 1

Scalar quantities

Answer 1

Have a magnitude only

e.g. Speed

Question 2

Vector quantities

Answer 2

Have magnitude and direction

e.g. Velocity

Question 3

Distance

Answer 3

Total distance travelled (m)

Question 4

Displacement

Answer 4

Distance travelled in a specified direction from a given starting point

Question 5

Speed

Answer 5

Rate of change of distance

Speed = Distance/Time (ms-1)

Question 6

Velocity

Answer 6

rate of change of displacement

Velocity = Change in displacement/Change in time (ms-1)

Question 7

Acceleration

Answer 7

Rate of change of velocity

Acceleration = Change in velocity/Change in time

Question 8

Mass

Answer 8

The measurement of the amount of matter that an object contains (kg)

Question 9

Weight

Answer 9

The gravitational force exerted by earth on an object

Weight = Mass x Gravity (N)

Question 10

Displacement-Time graph

Answer 10

Displacement against time

Gradient = Velocity

Question 11

Velocity-Time Graph

Answer 11

Velocity against Time
Gradient = Acceleration
Area Under = displacement

Question 12

Acceleration-Time graph

Answer 12

Acceleration against time

Area under = Change in velocity

Question 13

Momentum

Answer 13

The amount of oomph an object has

Momentum = Mass x Velocity (kgms-1)

Question 14

Newton’s 1st Law

Answer 14

“An object will remain in a state of rest, or contiunue to move with a constant velocity unless acted upon by a resultant external force”

Question 15

Newton’s 2nd Law

Answer 15

“The acceleration of a body of constant mass is proportional to the resultant force applied to it and in the direction of the resultant force.”

Sum of forces = Mass x Acceleration (N)

Question 16

Newton’s 3rd Law

Answer 16

“While body A exerts a force on body B, body B exerts an equal and opposite force on body A”

Question 17

Principle of conservation of linear momentum

Answer 17

“In any interaction between bodies, momentum remains constant provided no resultant external force acts.”

Question 18

Newton’s 2nd Law in terms of momentum

Answer 18

“The resultant force exerted on a body is directly proportional to the rate of change of linear momentum.”

Force = Change in momentum / Change in time (N)

Question 19

Impulse

Answer 19

The change in momentum of a body caused by a resultant force

Impulse = Force x Change in time (Ns)

Question 20

Force-Time Graph

Answer 20

Force against time

Area under = Impulse (Change in momentum)