Question 290: Properties of Matter

Question

A stone of mass 20 g is projected from a rubber catapult of length 0.1 m and area of cross section 10$$-$$6 m2 stretched by an amount 0.04 m. The velocity of the projected stone is ______________ m/s.(Young's modulus of rubber = 0.5 $$	imes$$ 109 N/m2)

Accepted Answer

By energy conservation
$${1 \over 2}.{{YA} \over L}.{x^2} = {1 \over 2}m{v^2}$$
$${{0.5 	imes {{10}^9} 	imes {{10}^{ - 6}} 	imes {{(0.04)}^2}} \over {0.1}} = {{20} \over {1000}}{v^2}$$
$$	herefore$$ $${v^2} = 400$$
$$v = 20$$ m/s

Properties of Matter

A stone of mass 20 g is projected from a rubber catapult of length 0.1 m and area of cross section 10$-6 m2 stretched by an amount 0.04 m. The velocity of the projected stone is ______________ m/s.(Young's modulus of rubber = 0.5 \times$ 109 N/m2)

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