# A stone falls freely from rest and the total distance covered by it in the last second of its motion equals the distance covered by it in the first three seconds of its motion. The stone remains in the air for - (a) 6s (b) 5s (c) 7s (d) 4s

By Ritesh|Updated : November 8th, 2022

A stone falls freely from rest and the total distance covered by it in the last second of its motion equals the distance covered by it in the first three seconds of its motion. The stone remains in the air for 5s. The correct option is B 5s. Given that the stone falls from rest, so u = 0:

The final second's distance is now equal to the motion's first three seconds' worth of travel. Consequently, using the second law of motion, we obtain

d3 = 0 + ½ gt2

= ½ x 10 x 9

= 45

Use Sn = u + ½ a (2n - 1), to find distance covered at any nth second

St = u + (2t - 1) x 10/2

According to the question,

d3 = St

5 (2t - 1) = 45

t = 5s

### Relationship between speed, time, and distance

Distance is the sum of an object's movements, regardless of direction. The distance can be defined as the amount of space an object has covered, regardless of its starting or ending position.

Speed = Distance/Time – This reveals how quickly or slowly an object is moving. It gives the amount of time it took to travel a certain distance divided by the distance traveled.

Speed is inversely correlated with time and directly correlated with distance. Hence,

Distance = Speed X Time, and

Time = Distance / Speed, as the speed increases the time taken will decrease and vice versa.

Summary:

## A stone falls freely from rest and the total distance covered by it in the last second of its motion equals the distance covered by it in the first three seconds of its motion. The stone remains in the air for - (a) 6s (b) 5s (c) 7s (d) 4s

When a stone is at rest, it falls freely, covering the same amount of ground in the final second of its motion as it did in the previous three. The stone hangs in midair for five seconds. The formula to fine speed is speed = distance/ time. GradeStack Learning Pvt. Ltd.Windsor IT Park, Tower - A, 2nd Floor, Sector 125, Noida, Uttar Pradesh 201303 help@byjusexamprep.com