It has to do with we're the water is coming from and we're it's at like city or town
The answer is A. Friction
hope this helps :)
Answer:
(a) v = 3..6 m/s
(b) The rain falling downward has been able to affect the horizontal motion of the car by reducing it's velocity from 4 m/s to 3.6 m/s.
Explanation:
from the question we have the following:
mass of the car (Mc) = 24,000 kg
initial velocity of the car (u) = 4 m/s
mass of water (Mw) = 3000 kg
final velocity of the car (v) = ?
(a) we can calculate the final momentum of the car by applying the conservation of momentum where
initial momentum = final momentum
Mc x U = (Mc + Mw) x V
24000 x 4 = (24000 + 3000) x v
96,000 = 27000v
v =3.6 m/s
(b) The rain falling downward has been able to affect the horizontal motion of the car by reducing it's velocity from 4 m/s to 3.6 m/s.
Answer:
38.6 J
Explanation:
c = molar heat capacity of silver = 25.35 J/(mol °C)
m = given mass of silver = 9.00 g
M = Molar mass of silver = 108 g
n = Number of moles of silver
Number of moles of silver are given as
n = 0.0833
Q = Energy needed to raise the temperature
ΔT = Change in temperature = 18.3 °C
Energy needed to raise the temperature is given as
Q = n c ΔT
Q = (0.0833) (25.35) (18.3)
Q = 38.6 J
Kinetic energy = (1/2) (mass) (speed)²
Before slowing down, the car's speed is 25 m/s,
and its kinetic energy is ...
(1/2) (1,500 kg) (25 m/s)²
= (1/2) (1,500 kg) (625 m²/s²)
= 468,750 joules .
After slowing down, the car's speed is 15 m/s,
and its kinetic energy is ...
(1/2) (1,500 kg) (15 m/s)²
= (1/2) (1,500 kg) (225 m²/s²)
= 168,750 joules.
The car lost (468,750 - 168,750) = 300,000 joules of K.E.
The law of Conservation of Energy says:
That 300,000 joules had to go somewhere.
If it's a standard, gas-powered car, then the kinetic energy got
put into the brakes. The energy turned into heat, and the heat
was carried off in the air.
If it's a more modern electric or hybrid car, then the kinetic energy
spun the wheel motors, turning them temporarily into electrical
generators. The generators converted the kinetic energy into
electrical energy, which got put back into the car's batteries, and
could be used again. That's why electric cars use less gas.
