A woman lifts a barbell $2.0 \mathrm{m}$ in $5.0 \mathrm{s}.$ If she lifts it by the same distance in $10 \mathrm{s},$ the work done by her is

A particle is moved from $\left(0, 0\right)$ to $\left(a, a\right)$ under a force $\overrightarrow{F}=\left(3\hat{\mathrm{i}}+4\hat{\mathrm{j}}\right)$ from two paths. Path $1$ is $OP$ and path $2$ is $OQP$. Let $W_1$ and $W_2$ be the work done by this force in these two paths. Then

The $300 \mathrm{N}$ crate slides down the inclined curved path from $A$ to $B$ in the vertical plane as shown in the figure. If the crate has a velocity of $1.2 \mathrm{m} {\mathrm{s}}^{–1}$ down the inclined at point $A$ and $8 \mathrm{m} {\mathrm{s}}^{–1}$ at $B.$ Find the work done against friction during the motion.