# Short-Questions

Fast solutions for complex problems

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## Why velocity ratio is always greater than mechanical advantage in a simple machine?

The mechanical advantage(M.A) of a real machine is always less than its velocity ratio(V.R) because mechanical advantage decreases due to the friction and weight of moving parts of the machine whereas the velocity ratio remains constant.

### Is velocity ratio same as mechanical advantage?

Mechanical advantage is defined as the ratio of resistance overcomes to the effort applied. Velocity ratio of simple machine is the ratio of distance travelled by effort to the distance travelled by load in the machine.

When a machine its mechanical advantage is equal to its velocity ratio then the machine is called?

As velocity ratio or ideal mechanical advantage is a simple ratio of two distances, it also does not have the unit. For ideal or perfect machine, work output is equal to the work input.

Why velocity ratio has no unit?

Answer: Velocity ratio of simple machine is the ratio of distance travelled by the effort to the distance travelled by theload in the machine. As velocity ratio or ideal mechanical advantage is a simple ratio of two distances, it also does not have the unit. The friction is not involved in it.

## Why can a machine not be 100% efficient?

A machine cannot be 100 percent efficient because output of a machine is always less than input. A certain amount of work done on a machine is lost to overcome friction and to lift some moving parts of the machine.

### What is the formula of velocity ratio?

= dE / dL = ratio of the displacement of the effort to the displacement of the load. When the Velocity Ratio (VR) value of a machine is less than 1 then we can say that machine provides a speed gain.

What is velocity ratio formula?

The velocity ratio (V.R.) of a machine is the ratio of distance moved by the effort to distance moved by the load. Formula – Velocity Ratio = Distance moved by the effort / Distance moved by the load = y/x. The velocity of given machine can also be determined by assuming the machine to be ideal.

What does velocity ratio depend on?

The forces and motion are dependent on each other and are usually inversely proportional to each other. The output force is usually greater than the output while the output speed is less than the input speed. The ratio of input speed to the output speed is called the velocity ratio (VR) of a machine.

## Why is velocity ratio not affected by friction?

Explanation:because it is the ratio of distance, which is not affected by friction.

### What is the ratio of load to effort?

The ratio of the load to the effort is called the actual mechanical advantage of the machine. The VR of a machine is the ratio of the distance moved by the effort to the distance moved by the load.

Are machines 100% efficient?

Machines are not 100% efficient because some of the work done by a machine is used to overcome friction. So work output is always less than work input. The energy a machine produces is always less than the energy put into it (energy input). That is why 100% efficiency in machines shall not be possible.

What is the efficiency of a machine can a machine be 100% efficient?

## Why is the mechanical advantage less than the velocity ratio?

The mechanical advantage of a machine is always less than its velocity ratio.It is because mechanical advantage decreases due to the friction and weight of moving parts of the machine, but the velocity ratio remains constant.

### Which is the best definition of mechanical advantage?

Mechanical advantage is defined as the ratio of resistance overcomes to the effort applied. Velocity ratio of simple machine is the ratio of distance travelled by effort to the distance travelled by load in the machine.

What is the velocity ratio of a simple machine?

The simple machine requires force to do work. The resistive force to be overcome is called load and the force applied to overcome the load is called effort. Velocity Ratio. Velocity ratio of simple machine is the ratio of distance travelled by the effort to the distance travelled by theload in the machine.

How is the efficiency of a simple machine defined?

The efficiency of a simple machine is defined as the ratio of useful work done by machine (output work) to the total work put into the machine (input work). This note provides us with an information about mechanical advantage, velocity ratio and efficiency. Mechanical advantage is defined as the ratio of resistance overcomes to the effort applied.