m = mass of the partner which the cheerleader lifts = 59.6 kg
h = height to which the partner is lifted by the cheerleader = 0.749 m
g = acceleration due to gravity = 9.8 m/s²
work done by the cheerleader in lifting the partner is same as the potential energy gained by the partner.
W = work done by the cheerleader in lifting the partner
PE = potential energy gained
so W = PE
potential energy is given as
PE = mgh
hence
W = mgh
inserting the values in the above formula
W = 59.6 x 9.8 x 0.749
W = 437.5 J
this is the work done in lifting the partner once.
the cheerleader does this 30 times , hence the total work done is given as
W' = 30 W
W' = 30 x 437.5
W' = 13125 J
Answer: 4 ohms
Explanation:
For parallel connection we use this formula
R=equivalent resistance
R1=24 ohms
R2=8 ohms
R3=12 ohms
1/R=1/R1 + 1/R2 + 1/R3
1/R=1/24 + 1/8 + 1/12
1/R=(1x1+3x1+2x1) ➗ 24
Cross multiplying we get
24x1=(1x1+3x1+2x1) x R
24=(1+3+2) x R
24=6xR
Divide both sides by 6
24 ➗ 6=6xR ➗ 6
4=R
R=4 ohms
I am not sure about this one
