Give the magnitude and direction of the net force acting on

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lawsofmotion

#1

Give the magnitude and direction of the net force acting on
(i) a drop of rain falling down with a constant speed.
(ii) a cork of mass 10 g floating on water.
(iii) a kite skillfully held statibnary in the sky.
(iv) a car moving with a constant velocity of 30 km/h on a rough road.
(v) a high-speed electron in space far from all
gravitating (material) objects and free of electric and magnetic fields


#2

(i) As drop of rain is falling downward with a constant speed, therefore its acceleration is zero.
According to Newton’s second law of motion, net force acting on drop F = ma= 0.
(ii) In floating condition, the weight of the body is balanced by the upthrust. Therefore, net force acting on a cork floating on water = 0.
(iii) As kite is held Stationary in the sky, therefore acceleration of the kite is zero. Therefore, net force acting on the kite F = ma = 0.
(iv) As car is moving with a constant velocity, therefore its acceleration is zero i.e. a =0 therefore, net force acting on the car F = ma = 0.
(v) As electron is in a space where there is no electric field, magnetic field and gravitating (material)
objects, therefore no electric, magnetic and gravitational force is acting on it. Hence, net force acting on electron is zero