Subject Experts Solutions for Exercise 1: PRACTICE QUESTIONS (CLASSROOM WING)

A crowbar of length $1 \mathrm{m}$ is used to displace a body. Find its mechanical advantage, if the load arm is $0.25 \mathrm{m}$.

A see-saw of length $2 \mathrm{m}$ is pivoted at $50 \mathrm{cm}$  from one end in a public park. What is the effort applied at the near end to the fulcrum to lift a load of $150 \mathrm{N}$ at the far end to the fulcrum?

Find the mechanical advantage of the below figure:

A nut is placed in a nutcracker at $5 \mathrm{cm}$ from the fixed end. If the force experienced by the nut is $100 \mathrm{N}$ when a force of $20 \mathrm{N}$ is applied at the free end of the nut cracker, find the length of the nutcracker.   

 Anil has a two-wheeler that weighs $120 \mathrm{kg}$. After completing his work, he used to park his vehicle in the regular parking place which is in connected to the ground with a ramp of inclination $45°$. If the length of ramp $1 \mathrm{m}$, then calculate the work done by Anil to park the vehicle against gravity. $\left(g\mathit{=}10 \mathrm{m} {\mathrm{s}}^{-2}\right)$

Roopa observed that her mother is using a cutting plier instead of fire tongs to hold a hot container, and she prevented her from doing so. Why?

Explain why, a single-fixed pulley is used to lift a load even if its MA is equal to $1$?

How can we use third-order levers as machines even though their MA is less than one?