Answer: 480 kJ
Explanation: Energy = power · time
E = Pt = 4000 W · 120 s = 480 000 J
<span>This projectile has been thrown in an oblique movement, so it’s moving in x and in y at the same time. Vy varies due to gravity, and Vx is a constant as there is no gravity in the horizontal direction. In order to calculate Vx, you have to use the angle:
Vx=V*cosa=12m/s*cos(14.2)= 11.6m/s
So now you should use Vx the same way it is used in a uniform linear movement.
d=v*t
dx=vx*t
t=dx/vx=7m/(11.6m/s)=0.603s</span>
<span>covex object and concave eyepiece.</span>
Answer:
Explanation:
Speed is the distance covered over the time taken to do so.
s = d/t = 45 m / 3 s = 15 m/s
The only force on the system is the mass of the hoop F net = 2.8kg*9.81m/s^2 = 27.468 N The mass equal of the rolling sphere is found by: the sphere rotates around the contact point with the table.
So by applying the theorem of parallel axes, the moment of inertia of the sphere is computed by:I = 2/5*mR^2 for rotation about the center of mass + mR^2 for the distance of the axis of rotation from the center of mass of the sphere.
I = 7/5*mR^2 M = 7/5*m
Therefore, linear acceleration is computed by:F/m = 27.468 / (2.8 + 1/2*2 + 7/5*4) = 27.468/9.4 = 2.922 m/s^2
