ex. 2a q 16

Asked by nilesh.dhote74 | 30th Apr, 2020, 04:59: PM

Expert Answer:

a)

(i) Work done is same for both as both the people carry the same weight of water to the same height.

 

(ii) Power developed is

L e t space p o w e r space d e v e l o p e d space b y space f a t h e r space b e space P subscript f space a n d space t h a t space b y space a space b o y space b e space P subscript b

P subscript b over P subscript f equals fraction numerator begin display style bevelled W over t subscript b o y end subscript end style over denominator begin display style bevelled W over t subscript f a t h e r end subscript end style end fraction equals t subscript f a t h e r end subscript over t subscript b o y end subscript

P subscript b over P subscript f equals 2 over 3
P subscript b colon space P subscript f space equals 2 colon 3

b right parenthesis space M a s s space o f space w a t e r space l i f t e d space b y space b o t h space i s comma space

m subscript w space equals space rho cross times V space equals space 10 cubed space cross times open parentheses 20 close parentheses cross times 10 to the power of negative 3 end exponent space equals space 20 space k g space

H e n c e comma space w o r k space d o n e space i s comma space
W space equals space m subscript w g h space equals space 20 cross times 9.8 cross times space 20
W space equals 3920 space J space equals space 3.92 space k J

Answered by Shiwani Sawant | 30th Apr, 2020, 06:06: PM