Answer:
15s
Explanation:
Given parameters:
Distance traveled = 375m
Speed = 25m/s
Unknown:
Time taken = ?
Solution:
To solve this problem, we make time the subject of the speed equation.
Speed =
Time =
Now insert the parameters and solve;
Time =
= 15s
The answer is the Second one
Answer:
Therefore the surface area of the balloon is increased at 4 cm³/s.
Explanation:
The balloon is being filled with air at a rate of 10 cm³/s
It means the volume of the balloon is increased at a rate 10 cm³/s.
i.e 
Consider r be the radius of the balloon.
The volume of of a sphere is

Differentiate with respect to t



The surface of area of the balloon is(S) = 

Differentiate with respect to t


Putting the value of


Given that r = 5 cm
=4 cm³/s
Therefore the surface area of the balloon is increased at 4 cm³/s.
Answer:
The change on the second particle is
.
Explanation:
The period of revolution of the particle in the magnetic field is given by the formula as follows :

It is given that the magnetic field is uniform. The mass of the second particle is the same as that of a proton but thecharge of this particle is different from that of a proton.

If both particles take the same amount of time to go once around their respective circles. So,

So, the change on the second particle is
.
Answer:
Rutherford and atomic model are correctly matched.