Question

Gravity loss during rocket flight occurs because

• A. Thrust is less than drag
• B. Vehicle accelerates horizontally only
• C. Part of thrust is used to overcome weight
• D. Exhaust velocity is reduced

Hint:

Gravity loss is the velocity loss due to \[ \boxed{ \text{work done against the gravitational force.} } \] Longer burn times generally result in greater gravity losses.

Answer 1

The Correct Option is C

Step 1: Recall the concept of gravity loss. During powered flight, \[ \boxed{ \text{a portion of the engine thrust is continuously used to balance the rocket's weight.} } \]

Step 2: Identify the reason for gravity loss. Since part of the thrust is spent overcoming gravity rather than increasing velocity, \[ \boxed{ \text{the rocket experiences gravity loss.} } \] Therefore, \[ \boxed{\text{Part of thrust is used to overcome weight}} \] is the correct answer. Thus, \[ \boxed{(C)} \] is the correct answer.