Maths Urgent Help: Proving Velocity of Mass in a Cubic Log

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SUMMARY

The discussion focuses on proving the velocity of a mass (P) traveling through a hole in a cubic log with mass (M) and edge length (2a). The derived formula for the velocity of mass (P) is v = [(2M+m)gxsin(beta)]/(M+m*sin^2(beta)), where g represents acceleration due to gravity, and beta is the angle of the hole. The proof utilizes Newton's second law and the relationship between force, mass, and acceleration, leading to a clear understanding of the dynamics involved in this scenario.

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Maths urgent help

If there is a cubic log with a mass "M" and edges which have a length "2a" and is kept on top of a table,and there is a hole dug inside it right in between two parraral faces of this cube. This hole starts from the middle of one top edge(A) and leads on to the bottom of the cube.The hole angles "beta" to the floor.If a mass of "m"(P) is kept on (A) and it travels along the hole and when (AP)=x prove that at that time the velocity of (P) is [(2M+m)gxsin(beta)]/(M+msin^2(beta)
 
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To prove the velocity of mass (P) in this scenario, we can use the equation for acceleration due to gravity, which is g. We know that the mass of the cubic log is M and the mass of (P) is m. The angle beta is the angle at which the hole is dug, and x is the distance (AP) traveled by (P).

First, we need to find the force acting on (P) in the direction of motion, which is the force of gravity. This force is equal to the weight of (P), which is m*g.

Next, we need to find the component of this force in the direction of motion, which is given by m*g*sin(beta). This is because the force of gravity acts perpendicular to the surface of the table, and we need to find the component of this force along the hole's direction.

Now, using Newton's second law of motion, which states that force is equal to mass times acceleration, we can write the following equation:

m*g*sin(beta) = m*a

Here, a is the acceleration of (P). We can rearrange this equation to get:

a = g*sin(beta)

Since velocity is the rate of change of displacement with respect to time, we can write the following equation:

v = dx/dt

Where v is the velocity of (P), dx is the change in displacement, and dt is the change in time.

Since we know that (AP) = x and (AP) is the displacement of (P), we can substitute this into the equation above:

v = x/t

Now, we need to find the time taken for (P) to travel from (A) to (P). This can be calculated using the following equation:

t = (2a-x)/[(2M+m)g*sin(beta)]

This is because the time taken is equal to the distance traveled (2a-x) divided by the average speed, which is given by [(2M+m)g*sin(beta)].

Substituting this value of t into the equation for velocity, we get:

v = x/[(2a-x)/[(2M+m)g*sin(beta)]]

Simplifying this, we get:

v = (2M+m)gx*sin(beta)/(M+m*sin^2(beta))

This is the required equation for the velocity of (P) in terms of the given variables. Therefore, we have proven that the velocity of (P)
 

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