A bullet of mass 10 ~g is fired horizontally | vedclass

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

Question

(B) The work-energy theorem states that the work done by all forces equals the change in kinetic energy.$W_{total} = \Delta K = K_f - K_i$Here,the tot

Vedclass · Accepted Answer

$3755$

Vedclass · Answer

(B) The work-energy theorem states that the work done by all forces equals the change in kinetic energy.$W_{total} = \Delta K = K_f - K_i$Here,the total work done is the sum of work done by gravity $(W_g)$ and work done against air resistance $(W_{air})$.$W_g + W_{air} = \frac{1}{2} m v_f^2 - \frac{1}{2} m v_i^2$Given:Mass $m = 10 ~g = 0.01 ~kg$Initial velocity $u = 1000 ~ms^{-1}$Final velocity $v = 500 ~ms^{-1}$Height $h = 50 ~m$Gravity $g = 10 ~ms^{-2}$Work done by gravity $W_g = mgh = 0.01 	imes 10 	imes 50 = 5 ~J$Change in kinetic energy $\Delta K = \frac{1}{2} 	imes 0.01 	imes (500^2 - 1000^2)$$\Delta K = 0.005 	imes (250000 - 1000000) = 0.005 	imes (-750000) = -3750 ~J$Now,$W_g + W_{air} = \Delta K$$5 + W_{air} = -3750$$W_{air} = -3750 - 5 = -3755 ~J$The work done against air resistance is the magnitude of the work done by air resistance,which is $3755 ~J$.

Similar Questions

An image formed by a concave mirror of focal length $6 \ cm$ is $3$ times the size of the object. What is the distance of the object from the mirror in $cm$?

The molecular formula of diphenylmethane is $C_{13}H_{12}$. How many structural isomers are possible when one of the hydrogen atoms is replaced by a chlorine atom?

The lanthanide contraction is responsible for the fact that

We consider the radiation emitted by the human body. Which of the following statements is true?

The greenhouse effect is related to

Vedclass Test Series

Exam Paper Generator

Online Exam Module