Answer:
option (E) is correct.
Explanation:
Work done is defined as the product of force and the distance in the direction of force.
force, f = 100 N
Coefficient of friction, = 0.25
distance = 15 m
So, net force F = f - friction force
F = 100 - 0.25 x m g
Work = (100 - 0.25 mg) x d cosθ
For minimum work, the angle should be maximum.
So, the value of θ is 76°.
thus, option (E) is correct.
Answer:
you'll see rocks that have been there for years
Answer:
average speed of car is 40 km/h
Explanation:
if car goes 48 km per 1.2 hours , the car goes 40 km per hour. so average speed of car is 40km/h
Ventilation is very important because it helps remove the gas form people’s homes and schools and it redirects the random gas outside so it is less likely to hurt people
distance traveled by a uniformly accelerated bike is given as
![d = \frac{v_f + v_i}{2} (t)](https://tex.z-dn.net/?f=d%20%3D%20%5Cfrac%7Bv_f%20%2B%20v_i%7D%7B2%7D%20%28t%29)
here we know that
![v_f = 25 m/s](https://tex.z-dn.net/?f=v_f%20%3D%2025%20m%2Fs)
![v_i = 15 m/s](https://tex.z-dn.net/?f=v_i%20%3D%2015%20m%2Fs)
![t = 15 s](https://tex.z-dn.net/?f=t%20%3D%2015%20s)
now we will have from above equation
![d = \frac{15 + 25}{2} (15)](https://tex.z-dn.net/?f=d%20%3D%20%5Cfrac%7B15%20%2B%2025%7D%7B2%7D%20%2815%29)
![d = 20 (15) = 300 m](https://tex.z-dn.net/?f=d%20%3D%2020%20%2815%29%20%3D%20300%20m)
so it will cover the total distance of 300 m