By conservation of momentum, the initial recoil speed of the
rifle is:
u = 904kg * 0.0106 kg / 3.53 kg = 2.7146 m/s
The final recoil speed v is zero in a distance of d = 0.0346 m
So the rifle's acceleration is a = (0 - u^2) / 2*d = -2.7146^2 / 2*.0323
m/s^2
a = -114.07m/s^2
Answer: h = 0.30 m
Explanation:
A person jumping from height h would possess potential energy = m g h
which will convert completely into kinetic energy as person hits the ground. Now, the maximum energy absorbed by the person can be = 200 J
m = 67 kg
g = 9.8 m/s²
⇒ m g h = 200 J
⇒ h = 200 J / (67 kg × 9.8 m/s²) = 0.30 m
Hence, a person can land safely on both legs without breaking them from a height of 0.30 m only.
Newton's new “reflecting telescope” was more powerful than ... Before Newton, scientists primarily adhered to ancient theories on ... laws of motion laid the groundwork for classical mechanics. Newton's research on motion helped give credibility to the heliocentric view. Newton also helped pioneer telescopic innovations, and he is sometimes credited with inventing the first reflecting telescope. He also conducted experiments using the prism, and developed a theory about the nature of color and light.
Explanation:
The vertical component the velocity of the projectile is 15 m/s x sin 30 = 7.5 m/s.
The body is accelarating downwards at 10 m/s^2.
This means that every second its upward velocity reduces by 10 m/s.
So if the body is travelling upwards at 7.5 m/s then how long does it take for the velocity to become 0?
(7.5 m/s) / (10 m/s^2) = 0.75 s
