There are four key characteristics of the magnetic force on a moving charge.
First, Its magnitude is proportional to the magnitude of the charge.
Second, the magnitude of the force is also proportional
Third, the magnetic force depends on the particle’s
velocity.
Fourth, we find by experiment that the magnetic force
does not have the same direction as the magnetic field
but instead is always perpendicular to both
and the velocity
So, in a mathematical language this is given by:
So, this is a cross product. Therefore, applying the Right-hand rule:
The answer is:
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D. to the left of its velocity.
Explaining this in other words:
"The force </span>
is directed into the plane of the paper, so this is the direction of the proton"
Assuming that all energy of the small ball is transferred
to the bigger ball upon impact, then we can say that:
Potential Energy of the small ball = Kinetic Energy of
the bigger ball
Potential Energy = mass * gravity * height
Since the small ball start at 45 cm, then the height
covered during the swinging movement is only:
height = 50 cm – 45 cm = 5 cm = 0.05 m
Calculating for Potential Energy, PE:
PE = 2 kg * 9.8 m / s^2 * 0.05 m = 0.98 J
Therefore, maximum kinetic energy of the bigger ball is:
<span>Max KE = PE = 0.98 J</span>
Given:
rod of circular cross section is subjected to uniaxial tension.
Length, L=1500 mm
radius, r = 10 mm
E=2*10^5 N/mm^2
Force, F=20 kN = 20,000 N
[note: newton (unit) in abbreviation is written in upper case, as in N ]
From given above, area of cross section = π r^2 = 100 π =314 mm^2
(i) Stress,
σ
=force/area
= 20000 N / 314 mm^2
= 6366.2 N/mm^2
= 6370 N/mm^2 (to 3 significant figures)
(ii) Strain
ε
= ratio of extension / original length
= σ / E
= 6366.2 /(2*10^5)
= 0.03183
= 0.0318 (to three significant figures)
(iii) elongation
= ε * L
= 0.03183*1500 mm
= 47.746 mm
= 47.7 mm (to three significant figures)
Answer:
remains the same, but the apparent brightness is decreased by a factor of four.
Explanation:
A star is a giant astronomical or celestial object that is comprised of a luminous sphere of plasma, binded together by its own gravitational force.
It is typically made up of two (2) main hot gas, Hydrogen (H) and Helium (He).
The luminosity of a star refers to the total amount of light radiated by the star per second and it is measured in watts (w).
The apparent brightness of a star is a measure of the rate at which radiated energy from a star reaches an observer on Earth per square meter per second.
The apparent brightness of a star is measured in watts per square meter.
If the distance between us (humans) and a star is doubled, with everything else remaining the same, the luminosity remains the same, but the apparent brightness is decreased by a factor of four (4).
Some of the examples of stars are;
- Canopus.
- Sun (closest to the Earth)
- Betelgeuse.
- Antares.
- Vega.
