Question 182: Work, Energy and Power & Circular Motion

Question

A particle of mass $$100g$$ is thrown vertically upwards with a speed of $$5$$ $$m/s$$. The work done by the force of gravity during the time the particle goes up is

Accepted Answer

Kinetic energy at point of throwing is converted into potential energy of the particle during rise.
$$K.E = {1 \over 2}m{v^2} = {1 \over 2} 	imes 0.1 	imes 25 = 1.25\,J$$
$$W =  - mgh =  - \left( {{1 \over 2}m{v^2}} ight) =  - 1.25\,J$$
$$\left[ \, ight.$$ As we know, $$mgh = {1 \over 2}m{v^2}$$ by energy conservation $$\left. \, ight]$$

Answer

$$-0.5J$$

Answer

$$-1.25J$$

Answer

$$1.25J$$

Answer

$$0.5J$$

Work, Energy and Power & Circular Motion

A particle of mass $100g is thrown vertically upwards with a speed of 5 m/s$. The work done by the force of gravity during the time the particle goes up is

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