A stone is thrown upward from the top of a 59.4m high cliff with an upward velocity component of 19.6m/s how long is the stone in the air?
Correct answer: C. 6.00 s
- A. 4.00 s
- B. 5.00 s
- C. 6.00 s
- D. 7.00 s
Explanation
Taking upward as positive, the stone's height is h = 59.4 m + 19.6 m/s × t - 4.9 m/s^2 × t^2. Setting h = 0 gives t^2 - 4t - 12.12 = 0, so the positive root is about 6.0 s; the likely mistake is using only the upward-flight time, 19.6 m/s ÷ 9.8 m/s^2 = 2.0 s, and ignoring the fall from the cliff.
Last updated
About Projectile Motion
Projectile motion combines uniform horizontal motion with vertically accelerated motion under gravity, assuming air resistance is neglected. Questions use the components of initial velocity to find time of flight, maximum height, horizontal range and position, while distinguishing projectile motion from general circular or one dimensional motion.
Practise Force and Motion
1,416 free Force and Motion MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Physics questions like this
Physics is on 13 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
2 Balls are thrown from a running train ball A just dropped while ball B is thrown horizontal outwards. Which will reach the ground earlier?
A ball is just allowed to fall from the window of a moving train, it will hit the ground following a:
A ball is thrown into the air with certain velocity v making an angle with horizontal. If air resistance is neglected, then at maximum height its velocity is:
A basketball is thrown upward along a parabollic path. What is the ball's acceleration at its highest point?
A football is kicked at 45 degrees with horizontal with K.E of E. Its K.E. at highest point is