Correct Answer - A::B::C::D
`S=100m, t=10.54sec, m=50kg`
Themotion can be assumed to be uniform because acceleration is minimum
a. `Speed v=S/t=9.487 m/s`
So K.E. `=1/2mv^2=2250J`
`b. Weight `=mg=490J`
`given R=(mg)/10=49J`
So, work done against resistance
`W_F=-RS=-49xx100`
`rarr W_(Ff)=-4900J` c. To maintain her uniform speed she has to exert 4900J of energy to overcome friction.
`P=W/t`
`=4900/1054=465W`