Answer
Hint:For a car to make a successful turn on a curved road two forces acting on the car have to be equal. One is the centrifugal force and the other is the frictional force. If the centrifugal force is higher than the car will slide to the right and if the frictional force is higher the car will slide to the left and we will never attain the maximum speed.
Formula Used:
Frictional Force,${F_{Friction}} = \mu .{F_{Normal}}$ ,where $\mu $is the coefficient of friction, and ${F_{Normal}}$ is the normal force acting upon the two surfaces. Centrifugal force,${F_{Centrifugal}} = - \dfrac{{m{v^2}}}{R}$ ,where m=mass of the body, v= velocity, and R= radius of the circular motion.Complete step by step answer:
Thus, (B) is the right option.
Note:Here, we have to keep in mind the forces working in a circular motion. When making a turn the force working outward always has to be equal to the force working inward. Thus, equating both will surely give us our desired result.
A helicopter of mass 1000 kg rises with a vertical acceleration of 15 m s–2. The crew and the passengers weigh 300 kg. Give the magnitude and direction of the,
(a) force on the floor by the crew and passengers,
(b) action of the rotor of the helicopter on the surrounding air,
(c) force on the helicopter due to the surrounding air.
Given,
Mass of the helicopter, mh = 1000 kg
Mass of the crew and passengers, mp = 300 kg
Total mass of the system, m = 1300 kgAcceleration of the helicopter, a = 15 m/s2 Using Newton’s second law of motion, the reaction force R,
R – mpg = ma
= mp(g + a) = 300 (10 + 15) = 300 × 25 = 7500 N The reaction force will be directed upwards, the helicopter is accelerating vertically upwards. According to Newton’s third law of motion, the force on the floor by the crew and passengers = 7500 N, directed downward.(b)
Using Newton’s second law of motion, the reaction force R’ experienced by the helicopter can be calculated as,
R' - mg = ma
= m(g + a) = 1300 (10 + 15) = 1300 × 25 = 32500 N The reaction force experienced by the helicopter from the surrounding air is acting upward. Hence, as per Newton’s third law of motion, the action of the rotor on the surrounding air will be 32500 N, directed downward.
(c) The force on the helicopter due to the surrounding air is 32500 N, directed upwards.