Advertisements
Advertisements
Question
Give the magnitude and direction of the net force acting on a drop of rain falling down with a constant speed.
Advertisements
Solution
Since the raindrop falls downward at a constant velocity, its acceleration is zero. Therefore, according to Newton's first law of motion, the net force acting on the raindrop is zero, i.e., a = 0 Consequently, from the equation F = ma, we have F = 0.
APPEARS IN
RELATED QUESTIONS
The driver of a three-wheeler moving with a speed of 36 km/h sees a child standing in the middle of the road and brings his vehicle to rest in 4.0 s just in time to save the child. What is the average retarding force on the vehicle? The mass of the three-wheeler is 400 kg and the mass of the driver is 65 kg.
If the speed of the stone is increased beyond the maximum permissible value, and the string breaks suddenly, which of the following correctly describes the trajectory of the stone after the string breaks?
Name the physical quantity whose unit is ‘newton’.
A force F1 acts on a particle accelerating it from rest to a velocity v. Force F1 is then replaced by F2 which decelerates the particle to rest.
In an imaginary atmosphere, the air exerts a small force F on any particle in the direction of the particle's motion. A particle of mass m projected upward takes time t1 in reaching the maximum height and t2 in the return journey to the original point. Then.
A particle is found to be at rest when seen from a frame S1 and moving with constant velocity when seen from another frame S2. Mark out the possible options.
(a) Both the frames are inertial.
(b) Both the frames are non-inertial.
(c) S1 is inertial and S2 is non-inertial.
(d) S1 is non-inertial and S2 is inertial
A particle is observed from two frames S1 and S2. Frame S2 moves with respect to S1with an acceleration a. Let F1 and F2 be the pseudo forces on the particle when seen from S1 and S2, respectively. Which of the following is not possible?
State and explain the law of inertia (or Newton's first law of motion).
What do you mean by inertia of rest?
Give two examples of the following:
Inertia of rest
If a 5 N and a 15 N forces are acting opposite to one another. Find the resultant force and the direction of action of the resultant force.
When a bus suddenly takes a tum, the passengers are thrown outwards because of
Newton's first law of motion describes ______.
A car of mass m starts from rest and acquires a velocity along east `v = vhati (v > 0)` in two seconds. Assuming the car moves with uniform acceleration, the force exerted on the car is ______.
Block A of weight 100 N rests on a frictionless inclined plane of slope angle 30° (figure). A flexible cord attached to A passes over a frictonless pulley and is connected to block B of weight W. Find the weight W for which the system is in equilibrium.
A smooth sphere of radius R and mass M is placed on the smooth horizontal floor. Another smooth particle of mass m is placed on the sphere and a horizontal force F is applied on the sphere as shown. If the particle does not slip on the sphere then the value of force F is ______.
Two blocks A and B of masses m and 2 m, respectively, are held at rest such that the spring is in natural length. Find out the accelerations of both the blocks just after release.
Match the following.
| Column I | Column II |
| a. Newton’s I law | propulsion of a rocket |
| b. Newton’s II law | Stable equilibrium of the body |
| c. Newton’s III law | Law of force |
| d. Law of conservation of Linear momentum | Flying nature of bird |
If the net force on an object is zero, what happens?
An interstellar spacecraft, far away from the influence of any star or planet, is moving at high speed under the influence of fusion rockets (due to the thrust exerted by fusion rockets, the spacecraft is accelerating). Suddenly the engine malfunctions and stops. The spacecraft will ______.
