Answer:
13.5 ms
Explanation:
The sound wave travels with uniform motion in both cases, so the time taken to cover a distance d is given by:
where
d is the distance to cover
v = 340 m/s is the speed of sound in air
So for the people across the newsroom,
d = 4.7 m
So the time taken is
The radio waves instead travels with uniform motion at the speed of light:
So the time taken for them is
where
d = 82 km = 82,000 m
is the distance of the people who are 82 km away. Substituting,
Therefore, the difference in time is
We only need to look at Newton's 2nd law of motion:
Net force = (mass) x (acceleration)
If the net force on an object is zero, then either its mass or its acceleration must be zero. If it's called an "object", then its mass isn't zero, so its acceleration is zero.
To calculate velocity, divide distance traveled by the time it took to travel that distance and add direction.
So either number 1 or number 3
Gases - the atoms and molecules in gases are much more spread out, so they can easily be compressed.
Explanation:
Using Cosine rule, we have 5² = 3² + 4² - 2(3)(4)(cosx).
=> cosx = 0, x = 90°.
