Answer:
At 400 m the potential energy of the mountain climber doubled the initial value.
Explanation:
Given;
initial height of the mountain climber = 200 m
final height of the mountain climber, = 400 m
The potential energy of the mountain climber is calculated as;
Potential energy, P.E = mgh
At 200 m, P.E₁ = mg x 200 = 200mg
At 400 m, P.E₂ = mg x 400 = 400mg
Then, at 400 m, P.E₂ = 2 x 200mg = 2 x P.E₁
Therefore, at 400 m the potential energy of the mountain climber doubled the initial value.
<span>a = (v2 - v1)/t = (10 - 6)/2 = 2 m/sec/sec (average acceleration)</span>
To solve this problem we will use the concept of electric field, with which we will make the proportional comparison as we move away from the center. So we have the maximum electric field is given as,

Where,
Q = Charge
R = Radius
Electric field inside the sphere is given as,




Electric field outside the sphere is given as,



Therefore the possible values are 3.5cm and 9.9cm: The correct answer is D.
Answer:
force at the top will be 388 N which is nearly equal to 389
option (b) is correct
Explanation:
We have given velocity of the moving car v = 10 m/sec
Radius of the circular section r = 30 m
Mass of the passenger m = 60 kg
Acceleration due to gravity 
At the top normal force is given by 
So force at top will be 
So force at the top will be 388 N which is nearly equal to 389
So option (b) is correct
Answer:10.02 m/s
4.68 m/s
Explanation:
Given
height of building=4 m
time taken=1.5 s
(a)Let u be the initial velocity
using equation of motion



u=10.02 m/s
(b)Velocity of keys just before keys were caught



