Additional Physics 40 flashcards Jack Young's

Question 1

What will happen if the resultant force acting on a stationary object is zero?

Answer 1

The object will stay stationary.

Question 2

What is the unit of mass?

Answer 2

Kg

Question 3

How are force, mass and acceleration linked?

Answer 3

force=mass*acceleration

Question 4

Unit for force?

Answer 4

Newtons (N)

Question 5

Unit for acceleration?

Answer 5

metres per second squared

Question 6

Velocity units?

Answer 6

Metres per second (m/s)

Question 7

what does a horizontal line on a distance on a distance-time graph represent?

Answer 7

the object is stationary.

Question 8

what is the different between speed and velocity?

Answer 8

the velocity of an object is its speed in a given direction.

Question 9

what does the gradient of a velocity-time graph represent?

Answer 9

acceleration.

Question 10

What are the units for acceleration?

Answer 10

Metres per second squared

Question 11

what does a horizontal line on a velocity-time graph represent?

Answer 11

the object is moving at a constant velocity.

Question 12

how do you calculate the acceleration from a velocity-time graph?

Answer 12

use a = (v-u)/t where a=acceleration (m/s^2), v=final velocity (m/s), u=initial velocity (m/s) and t=time (s).

Question 13

what happens to the forces when a vehicle travels at a steady speed?

Answer 13

the resistive forces balance the driving force.

Question 14

which force are most of the resistive forces acting on a vehicle caused by?

Answer 14

air resistance.

Question 15

how is the breaking force affected by speed?

Answer 15

the bigger the speed the greater the breaking force required to stop it in a certain distance.

Question 16

what is ‘stopping distance’?

Answer 16

the distance the driver travels during the drivers reaction time (thinking distance), and the distance it travels under the breaking force (breaking distance)

Question 17

what three things can a drivers reaction time be affected by?

Answer 17

tiredness, drugs and alcohol.

Question 18

what happens to the temperature of the breaks when you apply them and why?

Answer 18

it increases because the work done by the friction force between the brakes and the wheel reduces the kinetic energy of the vehicle so the temperature of the brakes increase.

Question 19

what can braking distance be affected by?

Answer 19

poor weather (icy and wet conditions) and poor conditions of the vehicle (tyres and breaks).

Question 20

if an object moves through the fluid faster, what happens to the frictional force?

Answer 20

it will increase.

Question 21

what does a falling object initially accelerate?

Answer 21

due to the force of gravity.

Question 22

what will eventually happen to the resultant force of a falling object?

Answer 22

it will be zero.

Question 23

what is ‘terminal velocity’?

Answer 23

the speed an object reaches when the resultant forces are zero, measured in m/s.

Question 24

how do you calculate the weight of an object?

Answer 24

mass (kg) x gravity (N/kg) = Weight (N).

Question 25

what is ‘work done’?

Answer 25

when a force causes an object to move through a distance. W= F (N) x d (m).

Question 26

what is the unit for work done?

Answer 26

joules (J).

Question 27

what is transferred when work is done on an object?

Answer 27

energy.

Question 28

will the amount of work done to move an object across ice be smaller or greater than to move the same object the same distance across grass?

Answer 28

it will be smaller because there are less frictional forces to counteract.

Question 29

what is power and what are its units?

Answer 29

the work done or energy transferred in a given time P= E/t. The units are watts (w), energy are joules (J) and time in seconds (s).

Question 30

what are the units for gravitational field strength (g)?

Answer 30

N/kg.

Question 31

if the gravitational field strength on earth is 10 N/kg what is the weight of someone who has a mass of 70kg?

Answer 31

70kg X 10 N/kg=700 N (Weight = m x g).

Question 32

how are forces represented?

Answer 32

by an arrow, ideally from where the force originates.

Question 33

what is a resultant force?

Answer 33

when a single force replaces all of the existing forces, the resultant force has the same motion as all of the forces added together.

Question 34

what will happen of the resultant force acting on a stationary object is not zero?

Answer 34

the object will accelerate in the direction of the resultant force.

Question 35

what does the gradient of a distance-time graph represent?

Answer 35

constant speed (velocity).

Question 36

how do you calculate the speed (velocity) from a distance-time graph?

Answer 36

speed (velocity) is a distance/time so use the axis to find the distance. travelled and divide it by the time taken.