A body is thrown vertically upward with 45 m/s. Distance travelled by the body in 5th second is (g = 10 m/s2)

To solve this problem, we need to use the equations of motion.

The equation of motion that we will use is: s = ut + 0.5gt^2

Where: s = distance travelled u = initial velocity t = time g = acceleration due to gravity

Given: u = 45 m/s g = -10 m/s^2 (it's negative because the body is moving against the direction of gravity) t = 5 seconds

We need to find the distance travelled in the 5th second, not the total distance travelled in 5 seconds.

So, we will find the total distance travelled in 5 seconds and 4 seconds, and then subtract the two.

Total distance travelled in 5 seconds: s5 = ut + 0.5gt^2 s5 = 455 - 0.510*5^2 s5 = 225 - 125 s5 = 100 m

Total distance travelled in 4 seconds: s4 = ut + 0.5gt^2 s4 = 454 - 0.510*4^2 s4 = 180 - 80 s4 = 100 m

So, the distance travelled in the 5th second is s5 - s4 = 100 - 100 = 0 m.

Therefore, the body did not travel any distance in the 5th second. This is because the body reached its maximum height and started its downward journey.