Consider the following four cases of a person applying force to an object: (1) a force of 5 n directed parallel to the floor is pulling a box over a distance of 1 m. (2) a force of 5 n directed at an angle of 30^\circ ∘ with respect to the floor is pulling a box over a distance of 1 m. (3) a force of 10 n directed at an angle of 30^\circ ∘ with respect to the floor is pulling a box over a distance of 1 m. (4) a force of 10 n directed at an angle of 60^\circ ∘ with respect to the floor is pulling a box over a distance of 1 m. rank the amount of work done by the person in each case , in order from greatest to least.

3 > 4=1 > 2

Explanation:

As we know that ,work done by a force given as

W= F.d cosθ

F=Force

d= Displacement

θ=Angle between force and displacement

1)

Here θ= 0°

F= 5 N

d= 1 m

W= F.d cosθ

W= 5 x 1 x cos 0°

W= 5 J

2)

Here θ=3 0°

F= 5 N

d= 1 m

W= F.d cosθ

W= 5 x 1 x cos 30°

W= 4.33 J

3)

Here θ= 30°

F= 10 N

d= 1 m

W= F.d cosθ

W= 10 x 1 x cos 30°

W= 8.66 J

4)

Here θ= 60°

F= 10 N

d= 1 m

W= F.d cosθ

W= 10 x 1 x cos 60°

W= 5 J

8.66 J >5 J=5 J>4.33 J

3 > 4=1 > 2

one person pulls 90n one way and the other has 100n pulling the other way.

so the net force = 90 - 100 = -10n,

or the ans can be 10n if the picture shows -90n and 100n instead.

answer: 2×10^-2kg

explanation: density= mass per volume

vol=mass/density

converting to s.i units we have;

3÷1000kg = 0.003

1.5÷100m = 0.15

0.003/0.15 = 0.02kg