We know that a wave is a disturbance that transfers energy through matter or space There are two main types of waves: Mechanical and Electromagnetic. Water waves are mechanical. A mechanical wave is an oscillation of matter to transfers energy, but you always need a medium (substance such as: solid, liquid, gas, plasma) to transport it. The medium for water waves is, in fact, the water. For example, ripple in water is a surface wave. On the other hand, electromagnetic waves don't need a medium to transport, they can do it through the empty space. Then, this is the major characteristic that makes these two types of waves different.
Answer:
At an angle of 
Explanation:
Assume the river flows from East to West so for the swimmer to cross across it, assume he crosses it from West to East.
The resultant speed will be given by

Answer:
Answer is D. 8.04 x 10^4 J
Explanation:
1. D
2. A
3. D
4. B
5. C
6. B
7. D
8. C
9. B
10. D
All correct i promise you that
Answer:
Explanation:
Given
length of wire 
change in length 
mass of wire 
Young's modulus for silver 
load on wire 

change in length is given by

Where A=area of cross-section




also wire is the shape of cylinder so cross-section is given by




