Physics- Topic 2/ Motion and Forces- Newton

Question 1

Newton’s first law

Answer 1

An object at rest will remain at rest and an object in motion will remain in at a constant velocity until acted on by an unbalanced force.

Question 2

Newton’s second law

Answer 2

When forces are unbalanced/ a resultant force on an object or body doesn’t equal 0, the object will accelerate towards the direction of the resultant.

Question 3

Newton’s third law

Answer 3

For every action there is an equal opposite reaction. An object A exerts a force on B, object B will exert an equal for on A.

Question 4

When the resultant force is 0

Answer 4

The object moves at a constant speed or rest.

Question 5

When the resultant force is not 0

Answer 5

The object will change direction or accelerate

Question 6

Newton’s second law equation

Answer 6

Force(N) = Mass(Kg) x Acceleration (m/s^2)
F=MA

Question 7

Weight equation

Answer 7

Weight(N)= Mass (Kg) x gravitational field strength (N/Kg)
W=MG

Question 8

Resultant force

Answer 8

the difference between the forces, until only one or none equals different than zero

Question 9

Weight

Answer 9

Weight is the force on an object due to the gravitational pull and their mass.

Question 10

Difference between weight and mass.

Answer 10

Mass is the quantity of matter one can hold, and barely changes ( eating/ drinking) but weight changes due to the strength of gravity.

Question 11

Why do things fall

Answer 11

Due to weight not gravity

Question 12

Why do objects need different amount of force to move

Answer 12

Because a heavier object needs more force to be moved

Question 13

Investigate the relationship between force, mass and acceleration by varying the masses added to a trolly

Answer 13

1) Raise the ramp so that the troll moves by itself at a constant velocity to reduce friction.
2) Measure the length of the card and fasten it onto the troll
3) Weight the combined mass of the trolly and the card
4)Place line gates near the two ends of the ramp attached to a data logger
5) Place a start point marker
6) Add weights to the pulley ( make sure the pulley is tightly secured) and attach this to the card via a string
7) repeat this
8) Repeat this with added weights

Question 14

Reaction times

Answer 14

Touch = 0.15s
Sound= 0.17s
Sight = 0.25s

Question 15

Drugs affect reaction time

Answer 15

Stimulant e.g caffeine = heighten alertness
depressant e.g alcohol= reduce alertness

Question 16

Dangers of deceleration

Answer 16

Driver may lose control over the vehicle and the brakes my overheat.

Question 17

Stopping distance

Answer 17

Thinking distance + Braking distance

Question 18

Work done (J)

Answer 18

Force (N) x Distance (M)

Question 19

How is the stopping distance affected

Answer 19

By drugs, friction, speed, mass, tyre and road quality.

Question 20

Momentum

Answer 20

momentum is a quantity to describe an object with a mass in motion. Momentum (kg m/s)= mass (kg) xvelocity (m/s)

Question 21

Newtons second law momentum

Answer 21

force (N) = change in momentum (kg m/s) /time taken (s)

Question 22

How to measure human reaction times

Answer 22

The ruler dropping experiment

Question 23

collision newton’s 3rd law

Answer 23

When two objects collide the total momentum before the collision is equal to the total momentum after the collision. They both exert an equal but opposite force.