Question
A constant retarding force of 60 N is applied to a body
of mass 25 kg moving initially with a speed of 12 m s–1. How long does the body take to stop?Solution
Given that Retarding force, F = – 60 N Mass of the body, m = 25 kg Initial velocity of the body, u = 10 m/s2 Final velocity of the body, v = 0 Using Newton’s second law of motion, the retardation (a) produced in the body can be calculated as: F = ma – 60 = 25 × a ∴ a = −60/25 a = − 2.4 m/s2 Using the first equation of motion, the time (t) taken by the body to come to rest can be calculated as v = u + a t Therefore, t = -u/a = -12/-2.4 = 5 sec
A particle is fired with initial speed 30 m/s and lands back at same horizontal level. If its horizontal range is equal to 4.5 times the vertical height...
Which one of the following is the equation for Velocity Time relation?
Which of the following materials exhibits piezoelectric effect?
A car moving at 72 km/h is brought to rest in 10 seconds. What is its acceleration?
A nucleus with mass number A and atomic number Z undergoes β⁻ decay. Which of the following is correct about the daughter nucleus?
The movement of a train is an example of what type of motion?
A wire is stretched by a force such that it experiences a strain of 2 x 10-3. If Young’s modulus of the material is 2 x 1011 Pa,...
The energy that can harness heat stored below the earth's surface is known as –
A ball is projected from the ground at 45°. It strikes a vertical wall and rebounds with the same speed making the same angle on the other side. If th...
Relevant for Exams:
