Answer:21.45 m/s
Explanation:
Given
Mass of sport car=920 kg
Mass of SUV=2300 kg
distance to which both car skid is 2.4 m
coefficient of friction (
)=0.8
Let u be the initial velocity of both car at the starting of skidding
and they finally come to zero velocity


s=2.4 m

u=6.13 m/s
so before colliding sport car must be travelling at a speed of
(conserving momentum)
v=21.45 m/s
Explanation:
the other 40% is used to power the 60% making it only capable of 60% efficiency
Answer:
Power will be 0.2023 watt
And when amplitude is halved then power will be 0.0505 watt
Explanation:
We have given mass of the Piano wire m = 2.60 gram = 0.0026 kg
Length of wire l = 84 cm = 0.84 m
So mass density 
Tension in the wire T = 25 N
Frequency f = 120 Hz
So angular frequency 
And amplitude A = 1.6 mm = 0.0016 m
We have to find the generated power
Power is given by 
From the relation we can see that power 
So if amplitude is halved then power will be
times
So power will be equal to 
The answer to this question is D or the last one