At what time, t, will an object thrown vertically upward at 30 m/s reach its maximum height? (Take g = 10 m/s²)
A6 s
B1.5 s
C2 s
D3 s
Answer & Solution
Correct answer: D. 3 s
At maximum height, v = 0. Using v = u + at with u = 30, a = −g = −10: 0 = 30 − 10t → t = 3 s. The object spends 3 s going up and another 3 s coming back to the launch point (total flight time 6 s).
Related questions
In a velocity-time graph, the AREA UNDER the curve gives:In a distance-time graph, a STRAIGHT HORIZONTAL line means:A car braking uniformly decelerates from 20 m/s to rest with deceleration 5 m/s². The brakA train starts from rest (u = 0) and accelerates uniformly at a = 2 m/s² for t = 10 s. TheA car starting at u = 5 m/s accelerates uniformly at a = 2 m/s² for t = 4 s. Its final velA car accelerates from 10 m/s to 20 m/s in 5 seconds. Its acceleration is:A cab covers 60 km in 1.5 hours. Its AVERAGE SPEED is:A student runs once around a circular school playground of perimeter 400 metres and return