Gravitational Field Strength Between Two Planets

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What does Fig. 17.3 show?

Variation of gravitational field strength with distance from the centre of the Earth (correct)

Variation of kinetic energy with distance from the centre of the Earth

Variation of electrical energy with distance from the centre of the Earth

Variation of mass with distance from the centre of the Earth

What is the unit of the gravitational field strength g in Fig. 17.3?

N kg^-1 (correct)

m s^-2

J kg^-1

mJ kg^-1

What is the ratio of the mass of Earth to the mass of Mars?

1:3

dependent on the value of r when g = 0 (correct)

2:1

3:1

What is the purpose of a wind turbine?

To convert kinetic energy into electrical energy Signup and view all the answers

What is the unit of the kinetic energy of the air incident at the turbine per second?

MJ s^-1 Signup and view all the answers

What is the equation for the maximum input power P from the wind?

P = 1/3 tAv^2 Signup and view all the answers

What is the characteristic of the equation P = 1/3 tAv^2?

It is a homogeneous equation Signup and view all the answers

What is the physical quantity represented by the variable 't' in the equation P = 1/3 tAv^2?

Density of air Signup and view all the answers

What is the Cosmological principle based on?

The universe is isotropic, homogeneous and has universal laws of physics Signup and view all the answers

What is the purpose of using absorption spectral lines in astronomy?

To determine the relative velocity of distant galaxies Signup and view all the answers

What is the wavelength of the absorption spectral line observed in the laboratory?

280 nm Signup and view all the answers

What is the significance of the Hubble constant in astronomy?

It is used to determine the velocity of galaxies Signup and view all the answers

What is a characteristic of a black hole?

It has a massive centre Signup and view all the answers

What is the origin of the Universe according to the Big Bang theory?

The Universe evolved from the Big Bang Signup and view all the answers

Which organization manages OCR?

Cambridge Assessment Group Signup and view all the answers

Where should one contact for copyright queries related to OCR assessment materials?

First Floor, 9 Hills Road, Cambridge Signup and view all the answers

If OCR fails to correctly acknowledge or clear any third-party content, what stance do they take?

They will correct the mistake at the earliest opportunity Signup and view all the answers

What does OCR provide after each live examination series related to copyright information?

A copyright acknowledgements booklet Signup and view all the answers

What is the brand name of the organization that OCR is part of?

Cambridge Assessment Signup and view all the answers

How can one access the OCR Copyright Acknowledgements Booklet?

Download from the public website Signup and view all the answers

What is the input power to the wind turbine when the wind speed is 8.0 m s$^{-1}$?

1.2 MW Signup and view all the answers

What is the density of air used in the wind turbine calculation?

1.3 kg m$^{-3}$ Signup and view all the answers

What efficiency is used for each wind turbine in the wind farm calculation?

42% Signup and view all the answers

What is the required output power for the wind farm to produce?

50 MW Signup and view all the answers

On an incomplete Hertzsprung-Russell (HR) diagram, what is found at region A?

Red giants Signup and view all the answers

What is the surface temperature of the Sun?

5800 K Signup and view all the answers

What is the wavelength of the emitted light at maximum intensity for Beta Pictoris?

370 nm Signup and view all the answers

What needs to be sketched on Fig. 20.3?

Velocity v/s time graph Signup and view all the answers

What is meant by an elastic collision?

A collision where both kinetic energy and momentum are conserved Signup and view all the answers

Given that the mass of a helium atom is $6.64 × 10^{-27}$ kg, what is the magnitude of the momentum p of Y after the collision if its velocity is 610 m/s?

$6.64 × 10^{-24}$ kg m/s Signup and view all the answers

Why are only small amounts of helium found in the Earth’s atmosphere?

Helium atoms have a small mass and high velocity leading them to escape the atmosphere Signup and view all the answers

If the angle of deflection of X is 25° after the collision, what does this imply about the direction of the velocity of X?

It goes to the right Signup and view all the answers

How does the mass of a helium atom compare to typical atomic masses?

It is significantly smaller Signup and view all the answers

Using the kinetic theory of gases, what factor primarily explains why helium escapes Earth's atmosphere?

High kinetic energy of helium atoms Signup and view all the answers