The work done by the elephant to lift one log is the force multiplied by the height at which the log has been lifted:
![W=Fh=250 N \cdot 5 m=1250 J](https://tex.z-dn.net/?f=W%3DFh%3D250%20N%20%5Ccdot%205%20m%3D1250%20J)
And so, the total work done to lift the 7 logs is 7 times the work done to lift each log:
Answer:
A. 181.24 N
Explanation:
The magnitude of hte electrostatic force between two charged objects is given by the equation
![F=k\frac{q_1 q_2}{r^2}](https://tex.z-dn.net/?f=F%3Dk%5Cfrac%7Bq_1%20q_2%7D%7Br%5E2%7D)
where
k is the Coulomb's constant
q1, q2 are the magnitudes of the two charges
r is the separation between the charges
In this problem, we have:
is the magnitude of the 1st charge
is the magnitude of the 2nd charge
r = 2.5 cm = 0.025 m is the separation between the charges
Therefore, the magnitude of the electric force is:
![F=\frac{(9\cdot 10^9)(4.5\cdot 10^{-6})(2.8\cdot 10^{-6})}{(0.025)^2}=181.44 N](https://tex.z-dn.net/?f=F%3D%5Cfrac%7B%289%5Ccdot%2010%5E9%29%284.5%5Ccdot%2010%5E%7B-6%7D%29%282.8%5Ccdot%2010%5E%7B-6%7D%29%7D%7B%280.025%29%5E2%7D%3D181.44%20N)
So, the closest answer is
A) 181.24 N
Answer:
Explanation:
A common theory suggests that desert pavements are formed through gradual removal of sand and other fine particles by the wind and intermittent rains leaving behind the large fragments. The larger rock particles are shaken into place by actions of different agents such as rain, wind, gravity, and animals
Answer:
v_f = 0.87 m/s
Explanation:
We are given;
F_avg = -17700 N (negative because it's backward)
m = 117 kg
Δt = 5.50 × 10^(−2) s
v_i = 7.45 m/s
Now, formula for impulse is given by;
I = F•Δt = - 17700 x 5.50 × 10^(−2) = - 973.5 kg.m/s
From impulse momentum theory, we know that;
Change in momentum of particle is equal to impulse.
Thus,
Δp = I = m•v_f - m•v_i
Thus,
-973.5= 117(v_f - 7.45)
Thus,
-973.5/117 = (v_f - 7.45)
-8.3205 + 7.45 = v_f
v_f = - 0.87 m/s
We'll take absolute value as;
v_f = 0.87 m/s
The amount or cost that the user of the energy-efficient bulb save during 100h of use will be $0.319.
<h3>How to calculate the cost?</h3>
For the 11.0W bulb, it should be noted that the value will be:
= 11.0 × 100 × (1/1000) × 0.110
= $0.121
The 40W bulb will be:
= 40 × 100 × (1/1000) × 0.110
= $0.44
Therefore, the amount that will be saved will be:
= $0.44 - $0.121
= $0.319
Learn more about cost on:
brainly.com/question/25109150
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