Answer:
at the speed of light (
)
Explanation:
The second postulate of the theory of the special relativity from Einstein states that:
"The speed of light in free space has the same value c in all inertial frames of reference, where
"
This means that it doesn't matter if the observer is moving or not relative to the source of ligth: he will always observe light moving at the same speed, c.
In this problem, we have a starship emitting a laser beam (which is an electromagnetic wave, so it travels at the speed of light). The startship is moving relative to the Earth with a speed of 2.0*10^8 m/s: however, this is irrelevant for the exercise, because according to the postulate we mentioned above, an observer on Earth will observe the laser beam approaching Earth with a speed of
.
Answer:
3875J
Explanation:
Energy is defined as the power × time
And it's defined as
Power = IV - I- current and V- voltage
Now quantity of electricity; Q = I × t
Where I is current and t is time
Now Energy = I ×V×t = V× I×t = V× Q;
where Q is quantity of electricity 775C and V is 5.0volt
Hence 775 × (5) =3875J
Answer:
According to Archimedes principle the upthrust on the body is equal to the weight of the water displaced by the body. ... Here, the mass would be the net difference in the weight of the object.
Answer:
The acceleration of the wagon is 3 m/s².
To calculate the acceleration of the wagon, we use the formula below.
Formula:
F = ma............. Equation 1
Where:
F = horizontal Force
m = mass of the wagon
a = acceleration of the wagon.
make a the subject of the equation
a = F/m.............. Equation 2
From the question,
Given:
F = 30 N
m = 10 kg
Substitute these values into equation 2
a = 30/10
a = 3 m/s²
Hence, the acceleration of the wagon is 3 m/s².