Answer:
-7.89 * 10^(-9) C
Explanation:
Parameters given:
q1 = 2.42 nC = 2.42 * 10^(-9) C
Distance between q1 and q2 = 5.33 m
q3 = 1.0 nC = 1 * 10^(-9) C
Distance between q1 and q3 = 1.9 m
Distance between q2 and q3 = 5.33 - 1.9 = 3.43 m
The net force acting on q3 is:
F = F(q1, q3) + F(q2, q3)
F = (k*q1*q3)/1.9² + (k*q2*q3)/3.43²
F = (9 * 10^(9) * 2.42 * 10^(-9) * 1 * 10^(-9))/3.61 + (9 * 10^(9) * q2 * 1 * 10^(-9))/11.7649
F = 6.033 * 10^(-9) + 0.765*q2
If the net force is zero:
0 = 6.033 * 10^(-9) + 0.765*q2
-0.765*q2 = 6.033 * 10^(-9)
=> q2 = -[6.033 * 10^(-9)]/0.765
q2 = -7.89 * 10^(-9) C
 
        
             
        
        
        
Answer:
Diameter of Newton’s 5th ring = 0.30 cm
Diameter of Newton’s 15th ring = 0.62 cm
Diameter of Newton’s 25th ring = ?
From Newton’s rings experiment we infer that 
 D2n+m − D2n = 4λmR
For the 5th and 15th rings we have
D215 − D25 = 4λ * 10 * R _______ (1) (m = 10)
For 15th and 25th rings
D225 − D215 = 4λ * 10 * R _______ (2) (m = 10)
We equate the two derivatives
Equation (2) = Equation (1)
D225 − D215 = D215 − D25
D225 = 2D215 – D25
Substituting the values into the equation
D225 = 2 * 0.62 * 0.62 – 0.3 * 0.3 =0.6788 cm2
 D25 = 0.8239 cm
 
        
             
        
        
        
Answer:
time taken with speed 23 km/h will be 1.8 hours or 1 hour 48 minutes
Explanation:
Given:
Time is inversely proportional to the speed
mathematically,
t ∝ (1/r)
let the proportionality constant be 'k'
thus,
t = k/r
therefore, for case 1
time = 3 hr
speed = 14 km/hr
3 = k/14
also,
for case 2
let the time be = t
r = 23 km/h
thus, 
we have
t = k/23
on dividing equation 2 by 1
we get

or

or
t = 1.8 hr = or 1 hour 48 minutes ( 0.8 hours × 60 minutes/hour = 48 minutes)
 
        
             
        
        
        
The line at the bottom of the picture ... probably the first line on a list of choices  .. is the correct equation.
 
        
             
        
        
        
--  Toss a rock straight up.  The kinetic energy you give it 
with your hand becomes potential energy as it rises.  
Eventually, when its kinetic energy is completely changed 
to potential energy, it stops rising. 
--  When you're riding your bike and going really fast, you come
to the bottom of a hill.  You stop pedaling, and coast up the hill.
As your kinetic energy changes to potential energy, you coast
slower and slower.  Eventually, your energy is all potential, and
you stop coasting.
--  A little kid on a swing at the park.  The swing is going really fast
at the bottom of the arc, and then it starts rising.  As it rises, the
kinetic energy changes into potential energy, more and more as it
swings higher and higher.  Eventually it reaches a point where its
energy is all potential; then it stops rising, and begins falling again.