Dynamics And Space

Question 1

Scalars? (5)

Answer 1

Distance 
Speed
Energy
Mass 
Time

Question 2

Equation for displacement?

Answer 2

Displacement= velocity x time

Question 3

The gradient of a velocity time graph?

Answer 3

The gradient of a velocity time graph gives the acceleration.

Question 4

Perpendicular, along?

Answer 4

Mgcos(angle)

Question 5

Down, parallel?

Answer 5

Mgsin(angle)

Question 6

Momentum equation?

Answer 6

P=mv

Question 7

Units of momentum?

Answer 7

Kgms-1

Question 8

What is an inelastic collision?

Answer 8

When only momentum is conserved.

Question 9

What is an elastic collision?

Answer 9

When kinetic energy AND momentum are conserved.

Question 10

What type of collision are explosions?

Answer 10

Explosions are inelastic because only momentum is conserved.

Question 11

Impulse equation?

Answer 11

Ft=mv-mu

Question 12

Does impulse last for a long time?

Answer 12

No impulse lasts for a short time.

Question 13

What can the impulse equation show?

Answer 13

The impulse equation shows the change in momentum.

Question 14

What is a projectile?

Answer 14

An object with a forward motion through the air but also a downward motion due to gravity, resulting in a curved path.

Question 15

Equation for vertical velocity?

Answer 15

V=u+at

Question 16

Explain geostationary satellites:

Answer 16

They must be above the earth 35000 km to be in free fall and have an orbital period of 24 hours.

Question 17

How to determine gravitational field strength?

Answer 17

The larger the mass the larger the gravitational field strength.

Question 18

The effect of the moon on the earth?

Answer 18

The moon influences the tides on Earth because when two masses become in close proximity to each other a force of attraction is between them.

Question 19

Maxwells statement on light?

Answer 19

Speed of light in a vacuum has a fixed value.

Question 20

Einsteins observations (2)

Answer 20

The speed of light is constant in all frames of reference.

Galilean invariance is true in all frames of reference.

Question 21

What is Doppler effect?

Answer 21

The change in frequency observed when a source of sound waves is moving relative to an observer.

Question 22

Explain red shift:

Answer 22

When light from objects are moving away from us, it is shifted to the red end of the spectrum and have longer wavelengths.

Question 23

Red shift calculation for stars?

Answer 23

If the star is moving away the number will be positive, if it’s moving towards us it will be negative.

Question 24

What is Hubbles Law?

Answer 24

Hubbles Law is the relationship between the recession velocity of a galaxy and its distance from us.

Question 25

What has the law proved? (2)

Answer 25

That galaxies are moving away from us and the galaxies further away from us are moving faster.

Question 26

Percentage of dark matter in the universe?

Answer 26

25% of the universe is made up of dark matter and 5% of the universe is made up of normal matter.

Question 27

What has given us evidence of dark matter?

Answer 27

The masses and velocities of galaxies have given evidence of dark matter.

Question 28

What percentage of the universe is dark energy?

Answer 28

70% of the universe is made up of dark energy.

Question 29

What is dark energy causing?

Answer 29

Dark energy is believed to be able to overcome gravitational attractions and is causing the universe to have an accelerating expansion rate.

Question 30

How were temperature measurements gained? (2)

Answer 30

Temperature measurements were gained using cosmic background radiation. A satellite called the cosmic background explorer provided evidence of the temperature of the earth.

Question 31

What did the cosmic background explorer support evidence of?

Answer 31

The cosmic background explorer supports evidence of the Big Bang theory as it records information of the expansion and cooling of the universe following the Big Bang.

Question 32

Other evidence of the Big Bang? (2)

Answer 32

Even distribution of matter in the universe. An abundance of light elements such as Helium throughout the universe.

Question 33

Big Bang theory version: (3)

Answer 33

The Big Bang suggests the Universe began as a singularity then space expanded very quickly. This started the formation of atoms that soon led to form stars and galaxies. The universe is cooling while also expanding but in the beginning it was very small and hot.

Question 34

Range?

Answer 34

V=d/t and use the horizontal speed

Question 35

Explain the effect of increasing the angle of projection on the kinetic energy of the shot at release?

Answer 35

The kinetic energy is less because as the angle increases the speed decreases.