alleryA stone dropped from a height of 80 m falls freely (g = 10 m/s squared). How long does it take to reach the ground?
A8 s
B2 s
C4 s
D16 s
Answer & Solution
Correct answer: C. 4 s
From 80 = 0.5 x 10 x t squared, t squared is 16, so t = 4 s.
Keep practising Is Matter Around Us Pure?
Browse all Is Matter Around Us Pure? questions for CBSE Class 9, or explore more Science topics.
Related questions
Braking is the same, but the starting speed is doubled. Stopping distance becomes?A ball is tossed up and caught at the same spot after 4 s. What is its average velocity?A car straight on a road moves at a constant 20 m/s. What is its acceleration?A train moves at a steady 36 km/h. How far does it go in 10 s?A car travels at a steady 50 km/h for one minute. About how far does it go?Which unit of speed is commonly used for air and marine travel?A car slows from 30 m/s to 10 m/s in 4 s. What is the magnitude of its deceleration?The rate of change of acceleration with time is called what?