Answer: Physical changes only change the appearance of a substance, not its chemical composition. Chemical changes cause a substance to change into an entirely substance with a new chemical formula. Chemical changes are also known as chemical reactions.
Explanation:
Answer:
B= 55.6×10^(-7) Tesla
Explanation:
B= μoI/(2πr)
B: magnetic field strength
μo: permeability of free space and is equal to 4π×10^(-7) T.m/A
r: distance from the wire
I : current in the wire
B= (4π×10^(-7)×125)/(2π×4.5)
B= 55.6×10^(-7) Tesla
There's no such thing as a wave of white light. Every light wave with
a certain wavelength has some color. White light is a mixture of all
the different wavelengths with all of the different visible colors.
They're ALL there in white light. When they all enter your eye at
the same time, your brain gets the message of brightness with
no particular color, which we call "white light".
Answer:
Current through each phase Vp = 2.2A
Total three phase power Pt= 1.45kW
Power factor of the load pf = 1
Explanation:
i) Find current through each phase
Vp =220V (rms)
Z =100 Ω
I = Vp/Z
= 220/100
= 2.2A
ii) Find the total three phase power
for a resistive load, Power, P = VI
Power for each phase is given as:
P = 220 * 2.2
= 484 W
Total power TP =3* P
=484*3
= 1452W
=1.45kW
iii) Find the power factor of the load
Phase angle for a resistive load is 0.
α= 0
Hence, power factor of load = cos α
pf = cos 0
pf = 1
Answer:

Explanation:
<u>Instant Acceleration</u>
The kinetic magnitudes are usually related as scalar or vector equations. By doing so, we are assuming the acceleration is constant over time. But when the acceleration is variable, the relations are in the form of calculus equations, specifically using derivatives and/or integrals.
Let f(t) be the distance traveled by an object as a function of the time t. The instant speed v(t) is defined as:

And the acceleration is

Or equivalently

The given height of a projectile is

Let's compute the speed

And the acceleration

It's a constant value regardless of the time t, thus
