Convex Lenses are used to focus light and form a image. They are transparent.
They are one type of lenses. Different type of lenses are used to focus light differently. The basic lenses are concave and convex. Convex lenses converge light falling on it whereas concave lenses diverge light falling on it.
instantaneous speed of the car
Answer: I = 111.69 pA
Explanation: The hall effect is all about the fact that when a semiconductor is placed perpendicularly to a magnetic field, a voltage is generated which could be measured at right angle to the current path. This voltage is known as the hall voltage.
The hall voltage of a semiconductor sensor is given below as
V = I×B/qnd
Where V = hall voltage = 1.5mV =1.5/1000=0.0015V
I = current =?,
n= concentration of charge (electron density) = 5.8×10^20cm^-3 = 5.8×10^20/(100)³ = 5.8×10^14 m^-3
q = magnitude of an electronic charge=1.609×10^-19c
B = strength of magnetic field = 5T
d = thickness of sensor = 0.8mm = 0.0008m
By slotting in the parameters, we have that
0.0015 = I × 5/5.8×10^14 × 1.609×10^-19×0.0008
0.0015 = I×5/7.446×10^-8
I = (0.0015 × 7.446×10^-8)/5
I = 111.69*10^(-12)
I = 111.69 pA
1. Air pollution is a problem<span> because it can cause damage to animals, trees, plants, crops and water sources in the environment. </span>Pollution<span> in the </span>air<span> causes </span>problems<span> for aviation because it reduces visibility, while also being responsible for damaging buildings and other structures.
2. </span><span>The air we breathe has a very exact chemical composition; 99 percent of it is made up of nitrogen, oxygen, water vapor and inert gases. Air </span>pollution occurs<span> when things that aren't normally there are added to the air. A common type of air </span>pollution<span>happens when people release particles into the air from burning fuels.
3. </span>Pollution prevention (P2) is any practice that reduces, eliminates, or prevents pollution at its source. ... Reducing the amount of pollution produced means less waste to control, treat, or dispose of. Less pollution means less hazards posed to public health and the environment.
4. Why is it so important to have clean air?
Answer:
2.96 cm
Explanation:
By Hook's law
Force(F) = Spring constant(k) × Extension(d)
F = k × d
Force is the weight of the object, F = W = mg
So we get, mg = kd ⇒ m ∝ d
2.5 ∝ 1.68 --------------(1)
4.4 ∝ d' --------------(2)
From (1) & (2), 4.4/2.5 = d'/1.68
d' = 2.96 cm ⇒ the required extension.
