Mechanics

Question 1

a t u v

Answer 1

v = u + at

Question 2

a s t u

Answer 2

s = ut + 1/2at^2

Question 3

a s t v

Answer 3

s = vt - 1/2at^2

Question 4

a s u v

Answer 4

v^2 = u^2 + 2as

Question 5

s u t v

Answer 5

s = 1/2(u + v)t

Question 6

If the net force is 0 the object is in?

Answer 6

Equilibrium - it stays stationary or at a constant velocity

Question 7

The weight of an object is

Answer 7

mg - mass x 9.8

Question 8

If an object is accelerating downwards, the net force is

Answer 8

Weight - Tension/up thrust etc. = ma

Question 9

What force acts upwards at right angles to the region of contact?

Answer 9

Normal reaction/contact force

Question 10

To resolve in the x direction

Answer 10

rNcosR

Question 11

To resolve in y direction

Answer 11

rNsinR or rNcos(90-R)

Question 12

What is the coefficient of friction and what does it usually lie between

Answer 12

Mu, between 0.3 and 0.9

Question 13

What is limiting friction?

Answer 13

The greatest friction, just before an object is about to move.
F = mu x R

Question 14

An object falling freely under the force of gravity has what acceleration?

Answer 14

9.8 m/s^2

Question 15

An object projected upwards has what acceleration?

Answer 15

-9.8 m/s^2

Question 16

When an object is projected upwards, peaks and begins to fall, what is the velocity at the peak?

Answer 16

0m/s

Question 17

Equation for terminal velocity

Answer 17

R = kv or R = kv^2

Question 18

If object A exerts a force on object B, what force does object B exert on A?

Answer 18

A force of the same magnitude in the opposite direction

Question 19

When an object is in equilibrium, what are the forces equal to?

Answer 19

The upwards forces are equal to the weight.

The forces parallel to the plain are equal to each other.

Question 20

When an object is about to lift off the ground, what is R equal to?

Answer 20

0

Question 21

When are tension and friction on an object equal?

Answer 21

When it’s in equilibreum

Question 22

What is the tension when two particles are attached by a light in extensible string?

Answer 22

It is equal, and acts in opposite directions