We have a toy gun with a spring constant of 50 N/m. The spring is compressed by 0.2 m. If you neglect friction and the mass of the spring, at what speed will a 2 g projectile be ejected from the gun

Explanation:

The elastic potential energy of a spring is given by , where is the spring constant of the spring and is displacement from point of equilibrium.

When released, this potential energy will be converted into kinetic energy. Kinetic energy is given by , where is the mass of the object and is the object's velocity.

Thus, we have:

Substituting given values, we get:

answer: 802.3 kilo joules of energy represents 191.75 kilo calorie of energy.

explanation:

energy released during combustion of one mole methane = 802.3 kilo joules

if 1 kilo joule = 0.239006   kilo calorie

then ,802.3 kilo joule will be = 802.30.239006 kilo calorie

802.3 kilo joule = 191.75 kilo calorie

hence, the energy in kilo calorie is 191.75 kilo calorie.

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