Answer:
P.E = 0.068 J = 68 mJ
Explanation:
First we need to find the height attained by the ball toy. For this purpose, we will be using 3rd equation of motion:
2gh = Vf² - Vi²
where,
g = -9.8 m/s² (negative sign due to upward motion)
h = height attained by the ball toy = ?
Vf = Final Velocity = 0 m/s (since it momentarily stops at the highest point)
Vi = Initial Velocity = 3 m/s
Therefore,
2(-9.8 m/s²)h = (0 m/s)² - (3 m/s)²
h = (9 m²/s²)/(19.6 m/s²)
h = 0.46 m
Now, the gravitational potential energy of ball at its peak is given by the following formula:
P.E = mgh
P.E = (0.015 kg)(9.8 m/s²)(0.46 m)
<u>P.E = 0.068 J = 68 mJ</u>
IT WOULD act like an electromagnet even now
this same thing happens when we make use of solenoids. we have a wire wound around a hollow pipe , and that pipe would have air in it . as there is no natural vaccum here, the air will get ionised.. spreading charges .. around itself..
a) Work done = Net Kinetic Energy
= 1/2 x 50 kg x ((12m/s)^2 - (3m/s)^2)
= 0.5 x 50 Kg x (144 -9)(m/s)^2
= 3375 Kg (m/s)^2
b) Force = mxa
a = 120 N/50 Kg = 2.4 m/s^2
Using newtons third law of motion, we get-
V^2 - U^2 = 2 x a x S
S= (12^2-3^2)m^2/s^2/(2 x 2.4 m/s^2)
= 28.125 m
To resolve these forces we have to make use of the sines and cosines.
To resolve this force in 30 degree north of west, the answer will be
100*sin(30)
The answer will be 50N
Now to resolve the force acting 60 degree north of east
100* cos(60)
The answer will be 50N.
This also adds to the total force acting that is 50+50=100N. This is the way forces are resolved according to their specified angles.
