Answer:
The formula that links energy and power is: Energy = Power x Time. The unit of energy is the joule, the unit of power is the watt, and the unit of time is the second.
Explanation:
Surface tension can change with the change in a medium that is just above the layer of the liquid's surface.
Explanation:
Pouring any oil or oily compounds (such as kerosene) on the free surface of the water will reduce the surface tension.
in the atmosphere directly affects the surface tension of the liquid.
If we increase the temperature of the water, then there is a high possibility of the surface tension of the water getting reduced, due to the fact that the net force of attraction is decreased.
Mixing surfactants or emulsifiers into the water will decrease the surface tension.
If the water is subjected to electrification, then the surface tension will be reduced.
Answer:
56250 N
Explanation:
mass, m = 6000 kg
initial speed, u = 20 m/s
final speed, v = 5 m/s
distance, s = 20 m
Use third equation of motion

5 x 5 = 20 x 20 + 2 a x 20
25 = 400 + 40 a
a = - 9.375 m/s^2
Braking force, F = mass x acceleration
F = 6000 x 9.375
F = 56250 N
Answer:


Explanation:
Wave 1, 
Wave 2, 
Wave 3, 
Wave 4, 
The general equation of travelling wave is given by :

The value of
will remain the same if we take phase difference into account.
For first wave,



For second wave,



For the third wave,



For the fourth wave,



It is clear from above calculations that waves 1 and 3 have same time period. Also, wave 2 and 4 have same time period. Hence, this is the required solution.
Let A = i+j+k be a vector and B = 3 be any scalar,
Multiplying A and B,
AB = (i+j+k)3 = 3i+3j+3k
Which is a new vector whose direction is same as the old but it's 3 times greater in length than the old vector(i+j+k).
Now, dividing A and B,
A/B = (i+j+k)/3 =

Which is again a new vector whose direction is same as the old but now it's 1/3 times small in length than the old vector.
Direction is same because we multiplied by positive scalar. If we multiply A by suppose -1, -4, -1000000 or any negative number, it's direction will reverse.
Thus, if we multiply a vector with scalar, it's length increases. If we divide, it shrinks.