Third Law of Motion
Newton’s third law: the law of action and reaction “ Every action there is an equal and opposite reaction.“
A force of 5 N gives a mass m1, an acceleration of 10 m s–2 and a mass m2 , an acceleration of 20 m s-2 . What acceleration would it give if both the masses were tied together?
Solution: m1 = F/a1 ; andm2 = F/a2 . Here, a1 = 10 m s-2;a2 = 20 m s-2 and F = 5 N.Thus, m1 = 5 N/10 m s-2 = 0.50 kg; andm2 = 5 N/20 m s-2 = 0.25 kg.If the two masses were tied together,the total mass, m would be m = …
A motorcar is moving with a velocity of 108 km/h and it takes 4 s to stop after the brakes are applied. Calculate the force exerted by the brakes on the motorcar if its mass along with the passengers is 1000 kg.
Solution:The initial velocity of the motorcaru = 108 km/h= 108 × 1000 m/(60 × 60 s) = 30 m s-1and the final velocity of the motor carv = 0 m s-1.The total mass of the motorcar along with its passengers = 1000 kg and thetime taken to stop the motorcar, t = 4 s. we …
Which would require a greater force –– accelerating a 2 kg mass at 5 m s–2 or a 4 kg mass at 2 m s-2 ?
Which would require agreater force –– accelerating a 2 kg massat 5 m s–2 or a 4 kg mass at 2 m s-2 ? Thus, F1 = m1 a1 = 2 kg × 5 m s-2 = 10 N; and F2 = m2 a2 = 4 kg × 2 m s-2 = 8 N.⇒ F1 …
A constant force acts on an object of mass 5 kg for a duration of 2 s. It increases the object’s velocity from 3 m s–1 to 7 m s-1. Find the magnitude of the applied force. Now, if the force was applied for a duration of 5 s, what would be the final velocity of the object?
Solution:We have been given that u = 3 m s–1 and v = 7 m s-1 , t = 2 s and m = 5 kg. we have,F = m ( v – u ) / tSubstitution of values in this relation givesF = 5 kg ( 7 m s-1 – 3 m s-1) / …
Application of Newtons second law of Motion
Newton’s second law of motion is applied when there is unbalanced force acting on an object. In this case, unbalanced force means that the object is subjected to a force that is not zero. The more precise second law of motion is frequently applied to determine. Kicking a Football: A football kicker directs force in …
MATHEMATICAL FORMULATION OF SECOND LAW OF MOTION
MATHEMATICAL FORMULATION OF SECOND LAW OF MOTION Suppose an object of mass, m is moving along a straight line with an initial velocity, u. It is uniformly accelerated to velocity, v in time, t by the application of a constant force, F throughout the time, t. The initial and final momentum of the object will …
MATHEMATICAL FORMULATION OF SECOND LAW OF MOTION Read More »
What is momentum ? Write its S I and C G S unit of Momentum .
Definition of Momentum “A product of mass and velocity of a moving body is called Momentum.“ formula of Momentum Momentum = mass × velocity Mathematically, P = m x v Where , P = Momentum m = mass v = velocity Momentum is a Vector quantity because it has magnitude as well as Direction. S …
What is momentum ? Write its S I and C G S unit of Momentum . Read More »
Second Law of Motion
What is Newton’s Second Law of Motion?