Question

A toy rocket is launched straight up by using a spring. The rocket is initially pressed down on the spring so that the spring is compressed by 9 cm. If the spring constant is 830 N/m and the mass of the rocket is 50 g, how high will the rocket go? You may neglect the effects of air resistance. A 14.48 m B 6.86 m C 10.84 m D 3.91 m E 8.03 m

Answer 1

Answer:

B.6.86 m

Explanation:

Given that

Compression in spring ,x= 9 cm

Spring constant ,K= 830 N/m

Mass of the rocket ,m= 50 g = 0.05 kg   ( 1 kg = 1000 g)

Now by applying energy conservation

$\dfrac{1}{2}Kx^2=mgh$

$h=\dfrac{1}{2\times mg}kx^2$

Now by putting the values ( we are taking g= 9.81 m/s²)

$h=\dfrac{1}{2\times 9.81\times 0.05}\times 830\times 0.09^2$

h= 6.853 m

Therefore the answer is B.

B.6.86 m