Answer:
500 kg
Explanation:
It is given that,
The mass of a open train car, M = 5000 kg
Speed of open train car, V = 22 m/s
A few minutes later, the car’s speed is 20 m/s
We need to find the mass of water collected in the car. It is based on the conservation of momentum as follows :
initial momentum = final momentum
Let m is final mass
MV=mv

Water collected = After mass of train - before mass of train
= 5500 - 5000
= 500 kg
So, 500 kg of water has collected in the car.
Angle, θ2 at which the light leaves mirror 2 is 56°
<u>Explanation:</u>
Given-
θ1 = 64°
So, α will also be 64°
According to the figure:
α + β = 90°
So,
β = 90° - α
= 90° - 64°
= 26°
β + γ + 120° = 180°
γ = 180° - 120° - β
γ = 180° - 120° - 26°
γ = 34°
γ + δ = 90°
δ = 90° - γ
δ = 90° - 34°
δ = 56°
According to the law of reflection,
angle of incidence = angle of reflection
θ2 = δ = 56°
Therefore, angle θ2 at which the light leaves mirror 2 is 56°
gravitational potential is directly proportional to the height of the object relative to a reference line and is given as
PE = mgh
where m = mass of object , g = acceleration due to
gravity and h = height of the object above the reference line .
as the skydiver falls , its height above the ground decrease and hence the gravitational potential energy of the skydiver decrease.
as per conservation of energy , total energy of the skydiver must remain constant all the time . hence the decrease in potential energy appears as increase in kinetic energy by same amount to keep the total energy constant
KE + PE = Total energy
so as the skydiver falls , it gains speed and hence the kinetic energy of skydiver increase since kinetic energy is directly proportional to the square of the speed.
when the parachute opens, the skydiver experience force in upward which tries to balance the weight of the skydiver. hence the speed of the skydiver decrease until upward force becomes equal to the downward force. hence the kinetic energy decrease just after the parachute opens
Answer:
18.4615385 amps
Explanation:
The voltage V in volts (V) is equal to the current I in amps (A) times the resistance R in ohms (Ω):
Answer: a good level of body fat can be found using your weight and height as a reference.
Explanation: