Answer:
2.43J
Explanation:
Given parameters:
Mass of the arrow = 0.155kg
Velocity = 31.4m /s
Unknown:
Kinetic energy when it leaves the bow = ?
Solution:
The kinetic energy of a body is the energy in motion of the body;
it can be derived using the expression below:
K.E = 
m v²
m is the mass
v is the velocity
Solve for K.E;
K.E = x 0.155 x 31.4 = 2.43J
52m/s is the answer because before it was gonna accelerate it was 52 m/s
Answer:
F-ma
Explanation:
If you are speaking of objects like satellites, etc. then their mass is much less than that of the Earth. A good approximation is Newton's first law of motion:
Force
=
Mass × Acceleration
often written:
F
=
m
a
The gravitational force is the same between the Earth and the object - only the mass differs. So the acceleration is inversely proportional to the mass.
So we can know what is in space maybe weird or interesting stuff
Answer:
7.98 m
Explanation:
In the given question,
distance above surface= 2 m
Distance penny from person = 8 m
Since the swimming pool is filled with water and atmosphere has air therefore the refractive index phenomenon will occur.
The refractive index of water: air is 4/3 (1.33).
Using the formula, 4/3 = real depth, apparent depth
real depth= 4/3 x apparent depth
Now, calculating apparent depth = 8 - 2
= 6 m
therefore, real depth = 4/3 x apparent depth
= 1.33 x 6
= 7.98
thus, 7.98 m is the real depth of water.
