Midterm Assesment

Question 1

Why do we have day and night?

Answer 1

Because the Earth rotates on its axis. It takes 24 hours to complete a full rotation which is why the day is 24 hours long.

Question 2

What makes a year 365 days?

Answer 2

This is because to complete a full rotation around the sun it takes 365 days

Question 3

What makes summer different from winter?

Answer 3

In the winter we are facing further away from the sun so the light is less concentrated in us. In the summer we are facing the sun so the light is more concentrated.

Question 4

When it is winter in Britain, what season is it in Australia, why?

Answer 4

In the winter the northern hemisphere it’s facing away from the sun but the lower hemisphere is facing towards the sun so it is summer for them and winter for us.

Question 5

What does a satellite orbit? What is the shape of that orbit?

Answer 5

Satellites orbit planets. There are natural satellites called moons and there are artificial satellites used for communication e.g. TV. They orbit in a slightly elliptical orbit

Question 6

What does a comet orbit? What is the shape of that orbit?

Answer 6

Comets orbit in a very elliptical orbit around the sun. The sun is not at the centre of their orbit,

Question 7

Why are the star in May different from the stars we see in December?

Answer 7

As the earth revolves around the sun the position of the earth changes and this creates different view of the night sky.

Question 8

What 3 things about an object can a force change?

Answer 8

Shape, speed and the direction of travel

Question 9

Name 3 forces acting in this room and one that doesn’t.

Answer 9

Gravity, contact force, friction and upthrust.

Question 10

What is Newton’s first law of motion?

Answer 10

An object at rest remains at rest and an object in motion remains in motion at a constant speed in a straight line unless acted on by an unbalanced force.

Question 11

A box has a 5N force acting on it pushing it to the left and a 4N force acting on it pushing it to the right. Calculate the force acting on it.

Answer 11

1N to the left

Question 12

Now both forces act downwards. What is the new resultant force?

Answer 12

9N

Question 13

Why are racing cars flat and smooth?

Answer 13

So there is less air resistance pushing it back and so it can glide easily through the air.

Question 14

If I want to reflect infra-red radiation when I go outside, what colour should my coat be?

Answer 14

Silver

Question 15

Removing the air from inside something creates a vacuum. Why is this hard to do in the lab?

Answer 15

Forming a perfect vacuum is impossible because no device can removes very single atom or molecule from a space. So it’s impossible to create a full vacuum.

Question 16

What causes water pressure on your goggles when you go underwater?

Answer 16

The deeper you go under the sea, the greater the pressure of the water pushing down on you as all the weight of the water above is being pushed on you.

Question 17

Why does a marshmallow grow when put in a vacuum?

Answer 17

In a vacuum most particles are removed from the air and the particles compact the marshmallow so when they are released the marshmallow is not compacted and doesn’t have the pressure particles pushing on it.

Question 18

If I put an object on a newtonmeter and get a reading of 32N, did I measure weight or mass?

Answer 18

Weight

Question 19

Going to the moon would change which one: weight or mass? Why?

Answer 19

Weight because wight is decided on how much gravity is there and mass is the body amount based that wont change on a different planet as it doesn’t use gravity to measure it.

Question 20

On Earth, what is gravitational field strength, g?

Answer 20

10 N

Question 21

On Earth, what does a mass of 12kg weigh?

Answer 21

120 N

Question 22

On Jupiter, where g=22 N/kg, what does the same mass weigh?

Answer 22

12kg

Question 23

What is the mass of an object with weight 4.5N on Earth

Answer 23

0.45kg

Question 24

Where would I go if I wanted to be weightless, and why?

Answer 24

Space because there is no gravity in space and do have wight there needs to be gravity

Question 25

What is the speed of an object that travels 100 metres in 20 seconds?

Answer 25

5 m/s

Question 26

What is the speed if it travels 100 metres in 1 minute?

Answer 26

1.66 m/s

Question 27

What equipment is needed to measure, what units: Force? Temperature?
Distance?
Time?

Answer 27

1. Newton Meter, newtons
2. Thermometer, Celsius
3. Meters , ruler, meter stick
4. Seconds , stop watch

Question 28

What is streamlining?

Answer 28

A form that presents very little resistance to a flow of air or water and increasing speed and ease of movement.

Question 29

What is a resultant force?

Answer 29

A resultant force is a system of forces acting on an object where the difference between the forces is the resultant force.

Question 30

What is infra-red radiation?

Answer 30

A heat radiation.

Question 31

What is the formula of finding pressure?

Answer 31

Pressure (pascal) = force (N)
————
area (m2)

Question 32

What is the formula to find mass?

Answer 32

Mass (kg) = weight (N)
—————
gravitational force (10N/kg)

Question 33

What is the formula to finding average speed?

Answer 33

Average speed (m/s) = distance (M)
——————-
time (S)

Question 34

What causes pressure in terms of atoms and particles?

Answer 34

Pressure comes from the collisions of particles with the container.