Artificial Satellites are always launched from the earth in the eastwards direction.

Question

Assertion (A): Artificial Satellites are always launched from the earth in the eastwards direction.

Reason (R): The earth rotates from west to east and so the satellite attains the escape velocity.

Choose the correct option.

1. A. Both A and R are individually correct and R is the correct explanation of A.
2. B. Both A and R are individually correct but R is not the correct explanation of A.
3. C. A is correct, but R is incorrect. (Correct answer)
4. D. A is incorrect but R is correct.

Correct Answer

Option C — A is correct, but R is incorrect.

Detailed Solution & Explanation

The correct answer is A is correct, but R is incorrect..

Key Points

• Assertion A is correct — satellites are launched eastward to benefit from Earth's rotational velocity (~465 m/s at the equator).
• However, the Reason is incorrect — satellites need orbital velocity (~7.9 km/s), not escape velocity (~11.2 km/s).
• Orbital velocity keeps a satellite in orbit; escape velocity would send it into space.

Additional Information

• The eastward launch exploits Earth's rotational speed, which is greatest at the equator (about 465 m/s) and falls to zero at the poles — the reason launch sites cluster near the equator.
• India's Satish Dhawan Space Centre at Sriharikota sits at roughly 13°N, and its east-facing coastline lets spent stages fall harmlessly into the Bay of Bengal.
• The exception proves the rule: satellites in polar or Sun-synchronous orbits are launched southward, forgoing the rotational bonus because the orbit requires it.