From a height of h above the ground, a ball i | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) Given initial speed $u = 40 \,ms^{-1}$ and angle $	heta = 30^{\circ}$.The final speed $v = 1.25 	imes u = 1.25 	imes 40 = 50 \,ms^{-1}$.Using t

Vedclass · Accepted Answer

$45$

Vedclass · Answer

(D) Given initial speed $u = 40 \,ms^{-1}$ and angle $	heta = 30^{\circ}$.The final speed $v = 1.25 	imes u = 1.25 	imes 40 = 50 \,ms^{-1}$.Using the principle of conservation of energy, the total mechanical energy at the point of projection and at the point of striking the ground remains constant.Taking the ground as the reference level for potential energy $(PE = 0)$:$E_{initial} = E_{final}$$\frac{1}{2} m u^2 + mgh = \frac{1}{2} m v^2$Dividing by $m$ and multiplying by $2$:$u^2 + 2gh = v^2$Substitute the given values:$(40)^2 + 2 	imes 10 	imes h = (50)^2$$1600 + 20h = 2500$$20h = 2500 - 1600$$20h = 900$$h = \frac{900}{20} = 45 \,m$.Thus, the value of $h$ is $45 \,m$.

From a height of $h$ above the ground, a ball is projected up at an angle $30^{\circ}$ with the horizontal. If the ball strikes the ground with a speed of $1.25$ times its initial speed of $40 \,ms^{-1}$, the value of $h$ is (acceleration due to gravity $= 10 \,ms^{-2}$) (in $\,m$)

Similar Questions

The energy required to accelerate a car from $10 \ m/s$ to $20 \ m/s$ is how many times the energy required to accelerate the same car from rest to $10 \ m/s$?

$A$ body of mass $1 \ kg$ is under a force, which causes a displacement given by $x = \frac{t^3}{3}$ (in $m$). Find the work done by the force in the first second (in $J$).

$A$ car and a truck are moving with the same kinetic energy. If the same retarding force is applied to both by using brakes,what will be the distance traveled by both vehicles before coming to rest?

$A$ bullet of mass $10 \ g$ is fired with a velocity of $800 \ m/s$. After passing through a mud wall of thickness $1 \ m$,its velocity decreases to $100 \ m/s$. Find the average resistive force exerted by the mud wall in $N$.

$A$ particle of mass $m$ slides down along a frictionless inclined plane $AC$ as shown in the figure. The kinetic energy of the particle at point $C$ is:

Vedclass Test Series

Exam Paper Generator

Online Exam Module