Answer:
Explanation:
Given that,
A light bulb has a resistance of 2.9ohms
R = 2.9 ohms
And a battery of 1.5V is applied
V = 1.5 V
We want to find the rate of energy transformed
First we need to know what rate of energy is
Rate of energy implies that we want to find power. Power is the rate at which work is done
P = Workdone / time
Then,
In electronic, the power dissipated by a resistor is given as
P = V² / R
P = 1.5² / 2.9
P = 0.7759 W
P ≈ 0.776 W
So, the rate at which electrical energy transformed in the lightbulb is 0.776 Watts
It means you can do 550 Newton Meters of work every second. Power is the rate of doing work, I hope this helps
Answer:
The lighter frog goes higher than the heavier frog.
The lighter frog is moving faster than the heavier frog
Explanation:
If both frogs have the same kinetic energy when they leave the ground, the following equality applies:

Now, if the only force acting on the frogs is gravity, when they reach to the maximum height, we can apply the following kinematic equation:

When h= hmax, the object comes momentarily to an stop, so vf =0
Solving for hmax:

As the lighter frog, in order to have the same kinetic energy than the heavier one, has a greater initial velocity, it will go higher than the other.
As a consequence of both having the same kinetic energy, the lighter frog will be moving faster than the heavier frog.
Answer:
The change in gravitational potential energy of the hiker = 2869685 J
Explanation:
Potential Energy: This is the energy possessed by a body, due to its change in position in the gravitational field. The unit of potential energy is Joules (J)
From the question,
Change in gravitational potential energy = Energy of the hiker at the top of Mt. Whitney - Energy of the hiker at the floor of Death valley.
ΔEp = mgh₂ - mgh₁
ΔEp = mg(h₂-h₁)........................... Equation 1
Where ΔEp = change in Potential Energy of the hiker, m = mass of the hiker, g = acceleration due to gravity, h₁ = lowest point in Death valley, h₂ = Elevation of Mt. Whitney.
Given: m = 65.0 kg, h₁ = -85 m ( because is a valley), h₂ = 4420 m,
Constant: g = 9.8 m/s²
Note: The h₁ is negative because is below sea level.
Substituting into equation 1
ΔEp = 65×9.8×[4420-(-85)]
ΔEp = 637(4420+85)
ΔEp = 637(4505)
ΔEp = 2869685
ΔEp = 2869685 J.
Thus the change in gravitational potential energy of the hiker = 2869685 J
Answer:
The formula to calculate velocity in this case:
v = v0 + at
=> a = (v - v0)/t
= (50 - 0)/4
= 50/4 = 12.5 (m/s2)
Hope this helps!
:)