2. Mechanics

Question 0

Define acceleration

Answer 0

Acceleration = is defined as the change in velocity per unit time

a = delta V / delta t

Unit = ms -2

Question 1

Define displacement

Answer 1

Displacement = The distance travelled in a particular direction from a specified origin

Displacement = Velocity x Time

Question 2

What does the suvat-equations stand for?

Answer 2

S = distance (m)
U = initial velocity (ms -1)
V = final velocity (ms -1) 
A = acceleration (ms -2) 
T = time (s) 

Suvat only works when the acceleration of the body is constant

Question 3

What does g mean?

Answer 3

g = gravity = 9.81 ms -2

Question 4

What is the equation for the slope of gradient of a graph?

Answer 4

= rise / run = (y2 - y1) / (x2 - x1) = deltaY / delta X

Question 5

What does the area under an acceleration-time graph give you?

Answer 5

The change in velocity

Question 6

What does the gradient of a velocity-time graph give you?

Answer 6

The acceleration

Question 7

What does the area under a velocity-time graph give you?

Answer 7

The displacement

Question 8

List 5 types of forces

Answer 8

• Friction
• Normal or supporting or contact force
• Tension and compression
• Air resistance or drag
• Upthrust
• Lift
• Thrust
• Weight

Measured in Newtons (N)

Question 9

What is the equation for weight, gravity and mass?

Answer 9

Weight (W) = mass (m) x acceleration due to gravity (g)

W = mg

Question 10

What is meant by translational equilibrium?

Answer 10

Translational equilibrium is meant that the forces acting on the body, in all three dimensions, are balanced.

Question 11

State Newton’s first law of motion

Answer 11

Newtons 1st law states that a body will either remain at rest or move with constant velocity, unless acted on by an unbalanced force

Question 12

State Newton’s second law of motion

Answer 12

Newton’s 2nd law states that the rate of change of momentum of a body is proportional to the applied force and takes place in the direction in which the force acts

F = ma

Question 13

What is meant by linear momentum?

Answer 13

Linear momentum = the product of mass and velocity

Momentum = mass x velocity

P = mv

Question 14

What is meant by impulse?

Answer 14

Impulse is defined as the produce of a force and the time during which it acts

Impulse = F x deltaT = m x deltaV

Impulse is the change of momentum

Question 15

State Newton’s third law of motion

Answer 15

Newton’s 3rd law states that if body A exerts a force on body B, then body B exerts an equal and opposite force on body A

Question 16

What is meant by work?

Answer 16

Work is defined as the force times the distance moved in the direction of the force

W = Fscos0

W = Work (J)
F = Force (N)
s = Distance moved (m)
0 = Angle between the applied force and the direction of motion