Answer:
E. Kepler's second law says the planet must move fastest when it is closest, not when it is farthest away.
Explanation:
We can answer this question by using Kepler's second law of planetary motion, which states that:
"A line connecting the center of the Sun with the center of each planet sweeps out equal areas in equal intervals of time"
This means that when a planet is further away from the Sun, it will move slower (because the line is longer, so it must move slower), while when the planet is closer to the Sun, it will move faster (because the line is shorter, so it must move faster).
In the text of this problem, it is written that the planet moves at 31 km/s when is close to the star and 35 km/s when it is farthest: this is in disagreement with what we said above, therefore the correct option is
E. Kepler's second law says the planet must move fastest when it is closest, not when it is farthest away.
Answer:
The image distance is 17.56 cm
Explanation:
We have,
Height of light bulb is 3 cm.
The light bulb is placed at a distance of 50 cm. It means object distance is, u =-50 cm
Focal length of the lens, f = +13 cm
Let v is distance between image and the lens. Using lens formula :
So, the image distance is 17.56 cm.
Answer:
The gravitational acceleration of the planet is, g = 8 m/s²
Explanation:
Given data,
The distance the object falls, s = 144 m
The time taken by the object is, t = 6 s
Using the III equations of motion
S = ut + ½ gt²
∴ g = 2S/t²
Substituting the given values,
g = 2 x 144 /6²
= 8 m/s²
Hence, the gravitational acceleration of the planet is, g = 8 m/s²
