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:
<h2>0.2 m/s²</h2>
Explanation:
The acceleration of an object given it's mass and the force acting on it can be found by using the formula

f is the force
m is the mass
From the question we have

We have the final answer as
<h3>0.2 m/s²</h3>
Hope this helps you
<h3><u>Given</u><u>:</u><u>-</u></h3>
Force,F = 100 N
Acceleration,a = 5 m/s²
<h3><u>To</u><u> </u><u>be</u><u> </u><u>calculated:-</u><u> </u></h3>
Calculate the mass of the box .
<h3><u>Formula</u><u> </u><u>used:-</u><u> </u></h3>

<h3><u>Solution:-</u><u> </u></h3>

★ Substituting the values in the above formula,we get:



Answer:
q2 = -1.61*10^-5 C.
Explanation:
It was given that,
F = 0.985N
q1 = +8.40 X10-6 C
q2 = ?
r = 1.11 m
k = 9 x 10^9 (standard)
It generally follows that, if force is attractive, charge will be negative.
force, F = kq1q2/r^2
0.985 = 9*10^9*8.40*10^-6*q2/1.11^2
75600q2 = 0.985*1.11^2
75600q2 = 1.2136
q2 = 1.2136/75600 = 1.60529
q2 = -1.61*10^-5 C.