Earth and the Solar System

Complete Table 11.1 by adding the names of the three planets that are not given.

Calculate the orbital speed of Mars as it travels around the Sun.

orbital speed = ______ $\text{km / s}$

Describe the relationship between the distance of a planet from the Sun and its orbital period.

Describe the relationship between the distance from the Sun and the average surface temperature of a planet.

In your description, include any anomalies.

On Fig. 9.1, draw the orbits of Mercury and Mars. Label each orbit.

Explain why the comet at position 3 cannot be seen from Earth when Earth is at position 5.

State the name of the force that acts on the comet.

Describe how the strength of the force that acts on the comet changes as the comet moves from position 1 through position 3 to position 4.

Explain your answer.

description ______

explanation ______

Table 9.1 gives the orbital radius and the orbital speed of Earth and of Jupiter as each moves around the Sun.

Table 9.1

Earth completes more orbits of the Sun than Jupiter in the same time.

Calculate the number of orbits that Earth makes around the Sun in the time that Jupiter makes one orbit.

Show your working.

number of orbits = ______

State what causes this force, and state the direction of the force.

cause ______

direction ______

The average radius of the orbit of Venus is $1.1 \times 10^{11}\text{ m}$. It takes Venus $5400\text{ hours}$ to complete one orbit of the Sun.

Calculate the average orbital speed of Venus around the Sun.

speed = ______ $\text{m / s}$

Planet X is closer to the Sun than Venus.

State the name of planet X and state how its orbital speed around the Sun compares with the orbital speed of Venus.

name ______
speed ______

Venus is always $1.1 \times 10^{11}\ \text{m}$ from the Sun.

Calculate $T_V$.

$T_V$ = ______ $\text{s}$

State what causes the force acting on Venus.

State the name of this planet.

Compare the time that this planet takes to complete one orbit of the Sun with $T_V$ and explain the difference.

Determine the distance from the Sun to the centre of the Milky Way in kilometres (km).

distance = ______ $\text{km}$

It takes the Sun $2.3 \times 10^8\ \text{years}$ to complete one orbit around the centre of the Milky Way.

Calculate the speed $v$.

$v$ = ______ $\text{m / s}$

Fig. 8.1 shows these planets in alignment with the Sun. They rotate around the Sun in the direction shown.

Mark and label on Fig. 8.1 the positions of the three planets 110 days after the position shown in Fig. 8.1.

State what is meant by a 'moon'.

State what provides this force.

The orbit of the Earth around the Sun is an ellipse.

Describe what happens to the magnitude of the force that acts on the Earth as it moves in this elliptical orbit.