A boy’s catapult is made of rubber cord which is 42 cm long, with 6 mm diameter of cross section and of negligible mass. The boy keeps a stone weighing 0.02 kg on it and stretches the cord by 20 cm by applying a constant force. When released, the stone flies off with a velocity of 20 ms−1. Neglect the change in the area of cross-section of the cord while stretched. The Young’s modulus of rubber is closest to
(a)
104 Nm−2
(b)
103Nm−2
(c)
108 Nm−2
(d)
106 Nm−2
A boy’s catapult is made of rubber cord which is 42 cm long, with 6 mm diameter of cross section and of negligible mass. The boy keeps a stone weighing 0.02 kg on it and stretches the cord by 20 cm by applying a constant force. When released, the stone flies off with a velocity of 20 ms−1. Neglect the change in the area of cross-section of the cord while stretched. The Young’s modulus of rubber is closest to
(a)
104 Nm−2
(b)
103Nm−2
(c)
108 Nm−2
(d)
106 Nm−2
Question ID - 51169 | SaraNextGen Top Answer
A boy’s catapult is made of rubber cord which is 42 cm long, with 6 mm diameter of cross section and of negligible mass. The boy keeps a stone weighing 0.02 kg on it and stretches the cord by 20 cm by applying a constant force. When released, the stone flies off with a velocity of 20 ms−1. Neglect the change in the area of cross-section of the cord while stretched. The Young’s modulus of rubber is closest to
(a)
104 Nm−2
(b)
103Nm−2
(c)
108 Nm−2
(d)
106 Nm−2
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A boy’s catapult is made of rubber cord which is 42 cm long, with 6 mm diameter of cross section and of negligible mass. The boy keeps a stone weighing 0.02 kg on it and stretches the cord by 20 cm by applying a constant force. When released, the stone flies off with a velocity of 20 ms−1. Neglect the change in the area of cross-section of the cord while stretched. The Young’s modulus of rubber is closest to |
|||
|
(a) |
104 Nm−2 |
(b) |
103Nm−2 |
|
(c) |
108 Nm−2 |
(d) |
106 Nm−2 |
(
I)2 =
mv2
⇒ Y=
= 
= 2.3 
106 N/m2
So, order is 106.