GK
PHYSICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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A car shortly after a stoplight turns green.
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A car approaching a red light
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A car with the cruise control set at 80 km/h
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A car turning a curve at a constant speed
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Detailed explanation-1: -The correct option is (C) A car with the cruise control set at 80 km/h. Explanation: Velocity is a vector quantity. The velocity of the cruise is constant.
Detailed explanation-2: -Explanation: If there are no forces acting upon the object, then there is no acceleration. If there is no acceleration, then the object will move with a constant velocity. Mathematically, we can look at Newton’s second law and the formula for acceleration.
Detailed explanation-3: -The correct option is D An object moving with a constant velocity.
Detailed explanation-4: -Remember that acceleration is a change in speed. A car that is slowing down is decreasing its speed. It is also accelerating, because its speed is changing. Imagine a car being driven down a road.
Detailed explanation-5: -Correct answer: Explanation: If an object is moving with constant velocity, then its acceleration must be zero. We can then look at Newton’s second law. If the acceleration is zero, then the net force must also be zero.