Answer:
a) the magnitude of the force is
F= Q(
) and where k = 1/4πε₀
F = Qqs/4πε₀r³
b) the magnitude of the torque on the dipole
τ = Qqs/4πε₀r²
Explanation:
from coulomb's law
E = 
where k = 1/4πε₀
the expression of the electric field due to dipole at a distance r is
E(r) =
, where p = q × s
E(r) =
where r>>s
a) find the magnitude of force due to the dipole
F=QE
F= Q(
)
where k = 1/4πε₀
F = Qqs/4πε₀r³
b) b) magnitude of the torque(τ) on the dipole is dependent on the perpendicular forces
τ = F sinθ × s
θ = 90°
note: sin90° = 1
τ = F × r
recall F = Qqs/4πε₀r³
∴ τ = (Qqs/4πε₀r³) × r
τ = Qqs/4πε₀r²
Answer:
h = 4.04 m
Explanation:
Given that,
Mass of a child, m = 25 kg
The speed of the child at the bottom of the swing is 8.9 m/s
We need to find the height in the air is the child is able to swing. Let the height is h. Using the conservation of energy such that,

Put all the values,

So, the child is able to go at a height of 4.04 m.
Explanation:
Work cannot be increased by using a machine of some kind.
A heat pump is a device that puts out heat. It involves pumping a lever over and over to get energy so it can work.
Answer:
The correct answer is C.
Clarify any confusing information in the instructions.
Explanation:
The very first thing that we need before conducting a scientific investigation is a set of instructions which might include the following information:
-What we are experimenting on?
-How are we going to do it?
-What things are needed for it?
If there are any confusions in the instructions, the chances of making a mistake rises. So, it is very important to clarify the confusions found in the instructions before choosing things needed for the experiment and starting the experiment.