Answer:
2 /s north
Explanation:
Given that,
Velocity due North is 8 m/s and due south is 6 m/s
We need to find the magnitude and the direction of the resulting velocity.
Let North is positive and South is negative. When two velocities are in opposite direction, they adds up. So,
It is positive. So, it is in North direction.
Answer:
The correct option is (c).
Explanation:
Given that,
The energy of a photon is,
We need to tell the color of this light. We know that, the energy of a photon is given by :
Where
c is the speed of light
The wavelength of yellow light is approx 580 nm. Hence, we can say that this photon corresponds to yellow light.
Answer:
39.7 m
Explanation:
First, we conside only the last second of fall of the body. We can apply the following suvat equation:
where, taking downward as positive direction:
s = 23 m is the displacement of the body
t = 1 s is the time interval considered
is the acceleration
u is the velocity of the body at the beginning of that second
Solving for u, we find:
Now we can call this velocity that we found v,
v = 18 m/s
And we can now consider the first part of the fall, where we can apply the following suvat equation:
where
v = 18 m/s
u = 0 (the body falls from rest)
s' is the displacement of the body before the last second
Solving for s',
Therefore, the total heigth of the building is the sum of s and s':
h = s + s' = 23 m + 16.7 m = 39.7 m