Answer:
29.2 ft/s
Explanation:
The distance of the light's projection on the wall
y = 13 tan θ
where θ is the light's angle from perpendicular to the wall.
The light completes one rotation every 3 seconds, that is, 2π in 3 seconds,
Angular speed = w = (2π/3)
w = (θ/t)
θ = wt = (2πt/3)
(dθ/dt) = (2π/3)
y = 13 tan θ
(dy/dt) = 13 sec² θ (dθ/dt)
(dy/dt) = 13 sec² θ (2π/3)
(dy/dt) = (26π/3) sec² θ
when θ = 15°
(dy/dt) = (26π/3) sec² (15°)
(dy/dt) = 29.2 ft/s
D. compost bins because they recycle matter into a new form
Explanation:
- The law of conservation of matter is about the creation and how matter is being transferred. According to the law, the matter cannot be destroyed. The matter should always be transferred from one form to another in the universe. There is never destruction of matter happens. There is also one more point to it, as it cannot be destroyed it also cannot be created.
- Here in the options, option A tells us the creation which is not possible, option B says about the destruction of matter which is not true according to the law, C is about storing the matter which will not happen because its get transferred and D is the correct option because it talks about the recycle/ transfer of matter.
Answer:
So it will lift the mass by h = 17 m
Explanation:
As per energy conservation we know that

here we know that


now we have


so work done by the engine is 250 J
now we have



The lunar lander landed on the moon
Answer:
speed of white ball is 1.13 m/s and speed of black ball is 2.78 m/s
initial kinetic energy = final kinetic energy

Explanation:
Since there is no external force on the system of two balls so here total momentum of two balls initially must be equal to the total momentum of two balls after collision
So we will have
momentum conservation along x direction

now plug in all values in it

so we have

similarly in Y direction we have

now plug in all values in it

so we have


now from 1st equation we have



so speed of white ball is 1.13 m/s and speed of black ball is 2.78 m/s
Also we know that since this is an elastic collision so here kinetic energy is always conserved to
initial kinetic energy = final kinetic energy

