# Gravitation (NEET (NTA)-National Eligibility cum Entrance Test (Medical) Physics): Questions 41 - 44 of 84

Get 1 year subscription: Access detailed explanations (illustrated with images and videos) to 2142 questions. Access all new questions we will add tracking exam-pattern and syllabus changes. View Sample Explanation or View Features.

Rs. 550.00 or

## Question number: 41

» Gravitation » Kepler's Laws of Planetary Motion

MCQ▾

### Question

The semi-major axes of the orbits of mercury and mars are respectively 0.387 and 1.524 in astronomical unit. If the period of Mercury is 0.241 year, what is the period of Mars?

### Choices

Choice (4) Response

a.

3.9 years

b.

1.9 years

c.

1.2 years

d.

3.2 years

## Question number: 42

» Gravitation » Escape Velocity

MCQ▾

### Question

and denotes the escape velocity from the earth and another planet having twice the radius and the same mean density as the earth. Then which of the following is (are) wrong?

(1)

(2)

(3)

(4)

Select the correct answers with mark it according to the following codes:

### Choices

Choice (4) Response

a.

1.2 and 3 are correct

b.

1 and 4 are correct

c.

1 and 3 are correct

d.

1 and 2 are correct

## Question number: 43

» Gravitation » Energy

MCQ▾

### Question

A body of mass 250 kg falls on the earth from infinity. What will be its energy on reaching the earth? Radius of the earth is 6400 km and g = 9.8 m/s 2. Air friction is negligible.

### Choices

Choice (4) Response

a.

1.56 ⨯ 10 10 J

b.

2.27 ⨯ 10 10 J

c.

2.54 ⨯ 10 9 J

d.

1.27 ⨯ 10 9 J

## Question number: 44

» Gravitation » Orbital Velocity of a Satellite

MCQ▾

### Question

The speed with which the earth have to rotate on its axis so that a person on the equator would weigh the as much as present will be - (Take the equatorial radius as 6400 km. )

### Choices

Choice (4) Response

a.

b.

3 28 ⨯ 10 -3 rad/sec

c.

3 28 ⨯ 10 -4 rad/sec

d.