Physics - Study Mode
[#1251] A body falling through a liquid acquires a steady velocity is known as
Correct Answer
(C) Terminal velocity
Explanation
Solution: When an object falls through a fluid, it attains a constant velocity through its subsequent motion. This happens because the net force on the body due to gravity and fluid becomes zero. This constant velocity is termed as terminal velocity.
[#1252] The spoon dropped by an astronaut in a satellite will
Correct Answer
(C) Continue to follow the motion of the satellite
Explanation
Solution: An orbiting satellite is a projectile in the sense that the only force acting upon an orbiting satellite is the force of gravity. A satellite is acted upon by the force of gravity and this force does accelerate it towards the Earth. In the absence of gravity a satellite would move in a straight line path tangent to the Earth. In the absence of any forces whatsoever, an object in motion (such as a satellite) would continue in motion with the same speed and in the same direction. The force of gravity acts upon a high speed satellite to deviate its trajectory from a straight-line inertial path. Indeed, a satellite is accelerating towards the Earth due to the force of gravity. As far as spoon dropped by astronaut in a satellite is concerned, it continues to follow the motion of the satellite as there is inertia of motion acting upon it.
[#1253] Which one is not a part of Kepler's Law?
Correct Answer
(C) Law of speed
Explanation
Solution: Law of speed is not a part of Kepler's Law.
[#1254] Kepler's law of planetary motion states that the square of the time period is proportional to the
Correct Answer
(C) Cube of the semi-major axis
Explanation
Solution: The square of the time period of the planet is directly proportional to the cube of the semimajor axis of its orbit.
[#1255] Which of these is true of all simple machines?
Correct Answer
(C) Both A & B
Explanation
Solution: Simple machine make work easier and work input > work output.