Answer: (A) velocity = 2.8m/s
(B) Average force = 1.9536 Newtons
Explanation:
Find detailed explanation in the attached picture
Answer:

Explanation:
Given:
- frequency of the broadcast,

- we have the speed of the radiation equal to the speed of light,

The broadcast waves are the electromagnetic waves but it can travel only upto a hundred kilometers without any loss of information carried by it.
<u>The relation between the frequency and the wavelength:</u>



Answer:
speed of boat as

river speed is given as

Explanation:
When boat is moving down stream then in that case net resultant speed of the boat is given as
since the boat and river is in same direction so we will have

Now when boat moves upstream then in that case the net speed of the boat is opposite to the speed of the river
so here we have

as we know when boat is in downstream then in that case it covers 24 miles in 2 hours

also when it moves in upstream then it covers same distance in 3 hours of time



so we have speed of boat as

river speed is given as

To solve the problem it is necessary to apply the concepts related to Conservation of linear Moment.
The expression that defines the linear momentum is expressed as
P=mv
Where,
m=mass
v= velocity
According to our data we have to
v=10m/s
d=0.05m

Volume 
t = 3hours=10800s

From the given data we can calculate the volume of rain for 5 seconds

Where,
It is the period of time we want to calculate total rainfall, that is


Through water density we can now calculate the mass that fell during the 5 seconds:



Now applying the prevailing equation given we have to



Therefore the momentum of the rain that falls in five seconds is 