exercise 2 q. 4

Asked by nilesh.dhote74 | 29th Apr, 2020, 11:51: AM

Expert Answer:

(a) Mass of skier, m = 60kg

Consider g = 10 m/s2 ... (Given)

Loss in potential energy = mghA - mghB 

mg(hA –hB)

=60 x 10 x(75 - 15)

= 60 x 10 x60=3.6x104J

 
(b)  
K i n e t i c space e n e r g y space a t space B space equals space 75 percent sign space cross times space 3.6 space cross times 10 to the power of 4

space equals space 75 over 100 space cross times space 3.6 space cross times 10 to the power of 4 space equals space 27000 space J
W e space k n o w comma space
K i n e t i c space e n e r g y space equals space 1 half m v squared space

H e n c e comma space
27000 space equals space 1 half space cross times space 60 cross times v squared space
v squared space equals space 27000 over 30 space equals space 900 space
v space equals space 30 space m divided by s space

Answered by Shiwani Sawant | 29th Apr, 2020, 01:45: PM