Advertisements
Advertisements
प्रश्न
Three rigid rods are joined to form an equilateral triangle ABC of side 1 m. Three particles carrying charges 20 μC each are attached to the vertices of the triangle. The whole system is at rest in an inertial frame. The magnitude of the resultant force on the charged particle at A is.
विकल्प
zero
3.6 N
3.6`sqrt3` N
7.2 N
Advertisements
उत्तर
zero
Using, Fnet = ma,
a = 0 ⇒ Fnet = 0
As the whole system is at rest, the resultant force on the charged particle at A is zero.
APPEARS IN
संबंधित प्रश्न
A batsman hits a cricket ball which then rolls on a level ground. After covering a short distance, the ball comes to rest. The ball slows to a stop because ______.
Give the magnitude and direction of the net force acting on a drop of rain falling down with a constant speed.
Name the scientist who gave the laws of motion.
A moving bicycle comes to rest after sometime if we stop pedalling it. But Newton’s first law of motion says that a moving body should continue to move for ever, unless some external force acts on it. How do you explain the bicycle case ?
Is it possible for a particle to describe a curved path if no force acts on it? Does your answer depend on the frame of reference chosen to view the particle?
The figure shows a light spring balance connected to two blocks of mass 20 kg each. The graduations in the balance measure the tension in the spring. (a) What is the reading of the balance? (b) Will the reading change if the balance is heavy, say 2.0 kg? (c) What will happen if the spring is light but the blocks have unequal masses?

The acceleration of a particle is zero, as measured from an inertial frame of reference. Can we conclude that no force acts on the particle?
The force exerted by the floor of an elevator on the foot of a person is more than the weight of the person if the elevator is
(a) going up and slowing down
(b) going up and speeding up
(c) going down and slowing down
(d) going down and speeding up
State Newton's first law of motion.
Derive the relation between newton and dyne.
Name the different kinds of inertia an object can possess. Give an example of each.
A man riding on a car has ___________ Inertia.
Classify the types of force based on their application.
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 ______.
In a legend, the hero-kid kicked a toy pig so that it is projected with a speed greater than that of its cry. If the weight of the toy pig is assumed to be 5 kg and the time of contact 0.01 sec., the force with which the hero-kid kicked him was ______.
(Speed of cry = 330 m/s)
The masses of 10 kg and 20 kg, respectively, are connected by massless spring as shown in the figure. A force of 200 N acts on the 20 kg mass. At the instant shown, the 10 kg mass has acceleration of 12 m/s2. What is the acceleration of 20 kg mass?
(g = 10 m/s2)
This question has Statement 1 and Statement 2. Of the four choices given after the Statements, choose the one that best describes the two Statements.
Statement 1: If you push on a cart being pulled by a horse so that it does not move, the cart pushes you back with an equal and opposite force.
Statement 2: The cart does not move because the force described in statement 1 cancel each other.
What is the significance of Newton’s first law?
When does an object accelerate?
