The answer is D because instantaneous means at a particular point in time
As per the given Figure attached here we know that both charges q1 and q2 will apply same force on charge q3 and hence the resultant force due to both charges will be along Y axis vertically upwards
So here we know that

now from the above equation


so both of the charges will apply 0.288 N force on q3 charge along the line joining them
now the net force due to vector sum is given by

here we know that angle is

now we have


so net force on q3 is 0.46 N vertically upwards along +Y axis
Answer:
B
Explanation:
Heat increase molecular motion
Ngan's mass on earth is 85kg.
Ngan has a weight on Mars = 14.5 N
Ngan’s weight on Earth = 833.0 N
Ngan’s mass on Earth = ?
<span>Fg,earth = mg(earth)</span>
<span>M = Fg,earth </span><span>/ g(earth)</span>
<span>M = 833.0 N / 9.8 m/s2</span>
<span>M = 85 kg</span>
Explanation:
It is given that,
Mass of person, m = 70 kg
Radius of merry go round, r = 2.9 m
The moment of inertia, 
Initial angular velocity of the platform, 
Part A,
Let
is the angular velocity when the person reaches the edge. We need to find it. It can be calculated using the conservation of angular momentum as :

Here, 


Solving the above equation, we get the value as :

Part B,
The initial rotational kinetic energy is given by :



The final rotational kinetic energy is given by :



Hence, this is the required solution.