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:
Heat needed = 71.19 J
Explanation:
Here heat required can be calculated by the formula
H = mL
M is the mass of water and L is the latent heat of vaporization.
Mass of water, m = 31.5 g = 0.0315 kg
Latent heat of vaporization of water = 2260 kJ/kg
Substituting
H = mL = 0.0315 x 2260 = 71.19 kJ
Heat needed = 71.19 J
Answer:
Mass of larger cart will be 0.0213 m /sec
Explanation:
We have given mass of small cart 
Initial velocity of small cart 
Mass of larger block 
Initial velocity of larger cart 
After the collision velocity of smaller cart 
Now according conservation of momentum




Answer:
Price=$7×10⁷
Explanation:
Step 1: Estimate the volume of the pile,
Step 2: Multiply it by the density to get its mass
Step 2: Then multiply the mass by the price per gram to get the total price
So
The average pile dimensions are=45.7×45×172.7

Price=m×$10
Price=(7×10⁶)×$10
Price=$7×10⁷