Answer:

Explanation:
Net force by which man push the lawn mower is given as

now it is given that 37% of this force is vertically downwards
so we will have


now we also know that

here we have


Now work done by this force to move the lawn mower is given as



> Non-zero numbers (like 1,2,3,4...) are always significant
> A zero sandwiched between two non-zero numbers is always significant
> Trailing zeros in a decimal (not whole number like million) are always significant.
<span>0,020170 = 2.0170 × 10^-2
5 sig-figs
</span>
Answer:
Part a)

Part b)

Part c)
Speed is more than the required speed so it will reach the top
Explanation:
Part a)
As we know that there is no frictional force while block is moving on horizontal plane
so we can use energy conservation on the block



Part b)
If the track has average frictional force of 7 N then work done by friction while block slides up is given as



work done against gravity is given as



Now by work energy equation we have



Part c)
now minimum speed required at the top is such that the normal force must be zero



so here we got speed more than the required speed so it will reach the top