1.
Answer:
a) It is less
Explanation:
By energy conservation we can say that initial potential energy of both child must be equal to the final kinetic energy of the two child.
Since initially they are at same height so we will say that initial potential energy will be given as
and MgH
so the child with greater mass has more energy and hence smaller child will reach with smaller kinetic energy
2.
Answer:
b. The two speeds are equal.
Explanation:
As we know by mechanical energy conservation law we have


since both child starts at same height so here they both will reach the bottom at same speed
3.
Answer:
c. The two accelerations are equal
Explanation:
Since we know that average acceleration of the motion is given as

since here initial and final speeds are same so they both must have same average acceleration here.
Weight = mass*gravity. Hence mass = 980/9.8 = 100kg. Gravity of planet 2 = weight/mass = 3.6 m/s^2
Answer:
Total charge flow through the cooker is 21600 C
Explanation:
As we know that the current flow through the cooker is given by Ohm's law
here it is given as




now the charge flow through it is given as

total time is t = 8 hours


There are four key characteristics of the magnetic force on a moving charge.
First, Its magnitude is proportional to the magnitude of the charge.
Second, the magnitude of the force is also proportional
Third, the magnetic force depends on the particle’s
velocity.
Fourth, we find by experiment that the magnetic force

does not have the same direction as the magnetic field

but instead is always perpendicular to both

and the velocity
So, in a mathematical language this is given by:

So, this is a cross product. Therefore, applying the Right-hand rule:
The answer is:
<span>
D. to the left of its velocity.
Explaining this in other words:
"The force </span>

is directed into the plane of the paper, so this is the direction of the proton"
This is very good conceptual question and can clear your doubts regarding work-energy theorem.
Whenever force is perpendicular to the direction of the motion, work done by that force is zero.
According to work-energy theorem,
Work done by all the force = change in kinetic energy.
here, work done = 0.
Therefore,
0=change in kinetic energy
This means kinetic energy remains constant.
Hope this helps