P10-Force And Motion

Question 1

Whats Newtons Third Law

Answer 1

For every action,there is an opposite action.

Question 2

Whats an example of contact force?

Answer 2

Friction of a sliding box on the floor.

Question 3

Whats Newtons first law?

Answer 3

Something will remain stationery until a force acts on it

Question 4

Calculate the direction and size of the acceleration of the car if its mass is 1000 kg.

Answer 4

Resulant force forward=400N 1000kg and 400N

Force= mass(kg) x acceleration =400N=1000kg x 0.4 m/s acceleration=0.4m/s

Question 5

What force is needed to cause this lorry to accelerate to the right at 0.6 m/s2?

Answer 5

8000kg x 0.6 m/s =4800N

due to Force(N) = mass(kg) x acceleration (m/s(2)

Question 6

Whats Newtons second law?

Answer 6

The second law,of a force of 1N = 1kg= = 1m/s Force=mass x acceleration

Question 7

car travels a distance of 200 m in 40 s. Calculate its speed in:
i metres per second (m/s)

Answer 7

200 divide 4 = 5 (m/s)

Miles per hour would be
5 x 2.2 = 11

Question 8

A motorcycle changes its speed from 4 m/s to 12 m/s in 16 s. Calculate the
acceleration of the motorcycle.

Answer 8

12-4=8

16s/8= acceleration = 2 m/s

Question 9

Estimate
the acceleration of a car that reaches a top speed of 120 mph from a
stationary start

Answer 9

0 to 120mph

120mph to m/s = 120 mph/2.2 = 54.4 time taken estimate = 20 seconds =2.72 m/s acceleration

Question 10

typical human reaction time

Answer 10

around 0.3 seconds

Question 11

What are three factors affecting thinking distance of driver?

Answer 11

Alcohol Consumption,Sleep and Age

Question 12

Three factors that affect car braking distance?

Answer 12

tyre condition,road condition and car brakes.

Question 13

A car of mass 1200 kg slows down from 24 m/s to 8 m/s over a time of 4 s.
Whats the force exerted?

Answer 13

24-8 = 16m/s divide by 4s = 4(m/s 2)

4(m/s 2) x 1200kg = 4800 N

Question 14

Whats the equation for mometum?

Answer 14

Momentum (kg m/s) x mass (kg) x velocity (m/s)

Question 15

Why is mometum a vector quantity?

Answer 15

Momentum has a size(mangnitutude) and a direction