Answer:
Time period, 
Explanation:
We have,
The frequency of an FM radio station is 89.3 MHz.
It is required to find the period of the wave.
The reciprocal of frequency is called time period of a wave. It can be given by :

So, the period of the wave is
.
Answer:
The flux will be nine times as great.
Explanation:
The electric flux due to a charge Q located in the center of a sphere can be obtained using Gauss's law. Considering a Gaussian surface in the form of a sphere of radius r:

The electric field (E) is parallel to the surface vector (dS), so 

Since the electric flux is proportional to the square of the sphere's radius, if radius of sphere were tripled, the flux will be nine times as great.
The average speed will be:
Total distance travelled divided by time taken
Total distance (in metres)= 80+125+45=250
Total time (minutes) =10
250/10
=25
Thus Mary's average speed is 25 metres per minute.
Answer:
3.62 m and - 1.4 m
Explanation:
Consider a location towards the positive side of x-axis beyond the location of charge Q₂
x = distance of the location from charge Q₂
d = distance between the two charges = 2 m
For the electric field to be zero at the location
E₁ = Electric field by charge Q₁ at the location = E₂ = Electric field by charge Q₂ at the location


x = 1.62 m
So location is 2 + 1.62 = 3.62 m
Consider a location towards the negative side of x-axis beyond the location of charge Q₁
x = distance of the location from charge Q₁
d = distance between the two charges = 2 m
For the electric field to be zero at the location
E₁ = Electric field by charge Q₁ at the location = E₂ = Electric field by charge Q₂ at the location


x = - 1.4 m