A tennis player smashes a ball of mass m horizontally at a vertical wall. The ball rebounds at the same speed v with which it st
1 answer:
Answer:
The magnitude of change in momentum is (2mv).
Explanation:
The momentum of an object is given by the product of mass and velocity with which it is moving.
Let the mass of ball is m. A tennis player smashes a ball of mass m horizontally at a vertical wall. The ball rebounds at the same speed v with which it struck the wall.
Initial speed of the ball is v and final speed, when it rebounds, is (-v). The change in momentum is given by :
p = final momentum - initial momentum
So, the magnitude of change in momentum is (2mv).
You might be interested in
This question involves the concepts of the law of conservation of momentum and velocity.
The velocity of the eight ball is "5.7 m/s".
According to the law of conservation of momentum:
where,
m₁ = mass of number three ball = 5 g
m₂ = mass of the eight ball = 6 g
u₁ = velocity of the number three ball = 3 m/s
u₂ = velocity of the eight ball = - 1 m/s (negative sign due to opposite direction)
v₁ = final velocity of the three number ball = - 5 m/s
v₂ = final velocity of the eight ball = ?
Therefore,
(5 g)(3 m/s) + (6 g)(- 1 m/s) = (5 g)(- 5 m/s) + (6 g)(v₂)
<u>v₂ = 5.7 m/s</u>
<u></u>
Learn more about the law of conservation of momentum here:
Answer:
72
Explanation:
The displacement of an object can be found from the velocity of the object by integrating the expression for the velocity.
In this problem, the velocity of the sport car is given by the expression
In order to find the expression for the position of the car, we integrate this expression. We find:
where C is an arbitrary constant.
Here we want to find the displacement after 3 seconds. The position at t = 0 is
While the position after t = 3 s is
Therefore, the displacement of the car in 3 seconds is
Newton's second law allows us to find the force of the block on the table is 126 N
Newton's second law says that the net force is proportional to the product of the mass and the acceleration of the body
Σ F = m a
Where the bold letters indicate vectors, m is the mass and the acceleration of the body
A free body diagram is a diagram where the forces are represented without the details of the bodies, in the attached we can see a free body diagram of the system.
Let's start by finding the acceleration of the elevator with kinematics
v = v₀ + a t
a =
Where v and v₀ are the current and initial velocity, respectively, at acceleration and t is the time
a =
a = 3.5 m / s²
Let's write Newton's second law for each body
The book
N₂ - W₂ + N₁ = m a
Table
N₁ - W₁ - W₂ = M a
W₁ = Mg
W₂ = mg
N₁ = (M + m) g + M a
N₁ = (10 + 2) 9.8 + 10 3.5
N₁ = 152.6 N
This is the reaction of the earth to the support of the block and the table
N₂ = ma + m g - N₁
N₂ = m ( a +g) - N₁
N₂ = 2 (3.5 + 9.8) - 152.6
N₂ = 26.6 - 152.6
N₂ = -126 N
The negative sign indicates that the direction is opposite to the one assigned, this is the action of the block on the table.
In conclusion using Newton's second law we can find the forces of the block on the table is 126 N
Learn more here: brainly.com/question/19860811
