When the car stops, inertia causes the person to continue forward at the speed of the car prior to stopping
Answer:
No
Explanation:
The force of tension exerted by the string on the rock acts as centripetal force, so its direction is always towards the centre of the circle.
However, the direction of motion of the rock is always tangential to the circle: this means that the force is always perpendicular to the direction of motion of the rock.
As we know, the work done by a force on an object is

where
F is the magnitude of the force
d is the displacement of the object
is the angle between the force and the displacement
In this situation, F and d are perpendicular, so
, therefore
and the work done is zero:

In physics and chemistry, the law of conservation of energy states that the total energy of an isolated system remains constant; it is said to be conserved over time. This law means that energy can neither be created nor destroyed; rather, it can only be transformed or transferred from one form to another.
Answer:
Zero
Explanation:
Two long parallel wires each carry the same current I in the same direction. The magnetic field in wire 1 is given by :

Magnetic force acting in wire 2 due to 1 is given by :


Similarly, force acting in wire 1 is given by :
According to third law of motion, the force acting in wire 1 will be in opposite direction to wire 2 as :

So, the total magnetic field at the point P midway between the wires is in what direction will be zero as the the direction of forces are in opposite direction.