The car travels at a speed of 25m/s.
<u>Explanation:</u>
Given-
Mass, m = 1500kg
Coefficient of friction, μk = 0.47
Distance, x = 68m
Speed, s = ?
We know,

and
F = μ X m X g
Therefore,
μ * m * g = m * a
μ * g = a
Let, g = 9.8m/s²
So,


We know,

where, v is the final velocity
u is the initial velocity
a is the acceleration
s is the distance
If the car comes to rest, the final velocity, v becomes 0.
So,

The car travels at a speed of 25m/s.
Answer:
The gravitational force is definitely acting downwards towards the ground and this is equal to the weight of the skydiver.
the acceleration a = 7.8 m/s²
Explanation:
Given that :
the mass of the skydiver = 60 kg
Velocity = 50 m/s
Thus; gravitational force is definitely acting downwards towards the ground and this is equal to the weight of the skydiver.
Also; the air resistance is acting upward and the resultant of both forces = mass×acceleration
So;
mg-R = ma
60(9.8) - 120 = 60(a)
588 -120 = 60a
468 = 60a
a = 
a = 7.8 m/s²
Hence, the acceleration a = 7.8 m/s²
Answer:
due to the effect of gravity begins thermonuclear fusion processes, in these processes energy is released in the form of electromagnetic radiation
Explanation:
The Sun is a star of great size, which due to the effect of gravity begins thermonuclear fusion processes, in these processes energy is released in the form of electromagnetic radiation.
This radiation crosses the different layers of the Sun and escapes from it in the form of light that is emitted throughout the radiation spectrum, due to the temperature reached by the Sun about 5500K the most likely radiation is around 5500 nm corresponding to the green- yellow of the visible spectrum, but the entire spectrum is emitted with different intensity according to Stefan's law
In quantum mechanics this spectrum can also be analyzed as the emission of particles called photons, where each one is characterized by an energy and has a moment equal to zero, the energy of these photons is related to their frequency by the Planck equation
E = h f