Answer: The angle between force and displacement should be θ = 90° for minimum work. The angle between force and displacement should be θ = 0° for maximum work.
Answer:
v = 2.94 m/s
Explanation:
When the spring is compressed, its potential energy is equal to (1/2)kx^2, where k is the spring constant and x is the distance compressed. At this point there is no kinetic energy due to there being no movement, meaning the net energy in the system is (1/2)kx^2.
Once the spring leaves the system, it will be moving at a constant velocity v, if friction is ignored. At this time, its kinetic energy will be (1/2)mv^2. It won't have any spring potential energy, making the net energy (1/2)mv^2.
Because of the conservation of energy, these two values can be set equal to each other, since energy will not be gained or lost while the spring is decompressing. That means
(1/2)kx^2 = (1/2)mv^2
kx^2 = mv^2
v^2 = (kx^2)/m
v = sqrt((kx^2)/m)
v = x * sqrt(k/m)
v = 0.122 * sqrt(125/0.215) <--- units converted to m and kg
v = 2.94 m/s
The engine's efficiency is (35J)/125J) = 28% .
Do you have a different question to ask ?
What is the weight of a 4.2 kg bowling ball on Mars?
Answer:
1.59 kg
Explanation:
The formula is:
<u>F = G((Mm)/r2)
</u>
F is the gravitational force between two objects,
G is the Gravitational Constant (6.674×10-11 Newtons x meters2 / kilograms2),
M is the planet's mass (kg),
m is your mass (kg), and
r is the distance (m) between the centers of the two masses (the planet's radius).
Hope this helps
--Jay
