Well, we usually assume that the resistance of a circuit component
is constant and doesn't change. But the truth is that for anything
that conducts current, its resistance always increases somewhat
when it warms up.
For things like light bulbs, electric toasters, space heaters, electric
stove burners, the heat coils in a blow-dryer ... anything that's
designed to be really hot when it's doing its job ... the resistance
of those things increases significantly when they come up to their
operating temperatures.
Answer: 1 dioptre of power of a lens is defined as the unit of measuring the power of optical lens Or curved mirror which is equal to the reciprocal of the focal length. The focal length is measured in the meter. 1 dioptre is equal to 1/m where m is the focal length. Basically dioptre is the SI unit of optical power of the lens.
C. Three isotopes of the same element because the number of electrons and protons remain the same but the number of neutrons in the nucleus are different. This means that the isotopes have different masses to each other but the same chemical properties.
Answer:
the net toque is τ=8.03* 10⁻⁴ N*m
Explanation:
Assuming the disk has constant density ρ, the moment of inertia I of is
I = ∫r² dm
since m = ρ*V = ρπR² h , then dm= 2ρπh r dr
thus
I = ∫r²dm = ∫r²2ρπh r dr =2ρπh ∫r³ dr = 2ρπh (R⁴/4- 0⁴/4)= ρπhR⁴ /2= mR²/2
replacing values
I = mR²/2= 0.017 kg * (0.06 m)²/2 = 3.06 *10⁻⁵ kg*m²
from Newton's second law applied to rotational motion
τ= Iα , where τ=net torque and α= angular acceleration
since the angular velocity ω is related with the angular acceleration through
ω= ωo + α*t → α =(ω-ωo)/t = (21 rad/s-0)/0.8 s = 26.25 rad/s²
therefore
τ= Iα= 3.06 *10⁻⁵ kg*m²*26.25 rad/s² = 8.03* 10⁻⁴ N*m
Answer:
The correct option is;
B. Throughout all of history
Explanation:
A body of knowledge comprises of a given collection of concepts, activities and terms that represents a professional discipline that is outlined by the associated scholarly society, therefore, scientific knowledge, being comprised of very diverse field of knowledge, with different approaches and changing understanding is taking as a process of learning about the universe data collection, experimenting analysis and communication with a theme of systems, equilibrium, models and constant change which makes the basis of the body of scientific knowledge to be throughout all of history.
