A body projected vertically upwards with a velocity u returns to the starting point in 4 s. If g = 10 m s-2, the value of u in m/s is

Question

A body projected vertically upwards with a velocity u returns to the starting point in 4 s. If g = 10 m s-2, the value of u in m/s is (A) 10 (B) 5 (C) 4 (D) 20

Tardigrade Admin · Accepted Answer

Time of ascent = Time of descent = (4/2) = 2 s ν u + (-gt) i.e. 0 = u - 10 × 2 i.e. u = 20 m s-1

Q. A body projected vertically upwards with a velocity u returns to the starting point in $4 s$ . If $g = 10 m s^{- 2}$ , the value of $u$ in $m / s$ is

10

5

4

20

Time of ascent = Time of descent = $\frac{4}{2}$ = 2 s
$ν$ u + (-gt) i.e. 0 = u - 10 $\times$ 2 i.e. u = 20 m $s^{- 1}$

Q. A body projected vertically upwards with a velocity u returns to the starting point in 4s. If g=10ms−2, the value of u in m/s is

10

5

4

20

Time of ascent = Time of descent = 24​ = 2 s ν u + (-gt) i.e. 0 = u - 10 × 2 i.e. u = 20 m s−1

Q. A body projected vertically upwards with a velocity u returns to the starting point in $4 s$ . If $g = 10 m s^{- 2}$ , the value of $u$ in $m / s$ is

Time of ascent = Time of descent = $\frac{4}{2}$ = 2 s
$ν$ u + (-gt) i.e. 0 = u - 10 $\times$ 2 i.e. u = 20 m $s^{- 1}$