Answer:
a = v²/r
Explanation:
The acceleration of a body moving in a circular path is known as the centripetal acceleration. This is the acceleration of a body that keeps the body within the circular path. It is written in terms of the linear velocity v and the radius of the circle of rotation as shown;
a = v²/r where
v is the linear velocity
r is the radius
a is the centripetal acceleration
For these two questions, first you need to know that the voltage across each branch of a parallel circuit is the same.
So, for Q5, we can first find out the voltage across R₂ by V=IR.
Voltage across R₂ = 2.5 × 8 = 20V
Since R₂ and R₃ are in parallel circuit, their voltage should be the same. Thus, voltage across R₃ is 20V.
So, by V=IR,
current of R₃ =
= 5A
Q6. voltage across R₁ = 2 × 4 = 8V
∴voltage across R₂ = 8V
current of R₂ =
= 1A
<h3><u>Alternative method</u></h3>
From these two examples, you can find out that the current of each branch of the parallel circuit is inversely proportional to the resistance of the branch.
ie. for Q5,
= 
= 
I₃ = 5A
Q6.
= 
= 
I₂ = 1A
Answer:
3.76 m/s
Explanation:
Instantaneous velocity: This can be defined as the velocity of an object in a non uniform motion. The S.I unit is m/s.
v' = dx(t)/dt..................... Equation 1
Where v' = instantaneous velocity, x = distance, t = time.
Given the expression,
x(t) = 28.0 m + (12.4 m/s)t - (0.0450 m/s³)t³
x(t) = 28 + 12.4t - 0.0450t³
Differentiating x(t) with respect to t.
dx(t)/dt = 12.4 - 0.135t²
dx(t)/dt = 12.4 - 0.135t²
When t = 8.00 s.
dx(t)/dt = 12.4 - 0.135(8)²
dx(t)/dt = 12.4 - 8.64
dx(t)/dt = 3.76 m/s.
Therefore,
v' = 3.76 m/s.
Hence, the instantaneous velocity = 3.76 m/s
We can answer this one very quickly. From the <em>Law of Conservation of Energy</em>, we know that "Energy can't be created or destroyed.".
So that only leaves us one way to complete the sentence in this question:
"One form of energy can be <em>transformed into</em> another type of energy.
" <em>(B)</em>
Answer:
Due to Conservation of Energy just as the ball hits the ground it's potential energy is assumed zero
Therefore disregarding air resistance all energy is converted into potential energy.
So KE = PE
(5 J)