Answer:
n = 1.42
Explanation:
The refractive index for a medium is given by the ratio of the speed of light in vacuum to the speed of light in a medium.
So, the refractive index of the medium is 1.42.
Answer:
Simple machine: pair of tongs, seesaw and wheelbarrow
Compound machine: sewing machine, fishing rod and reel and crane.
Explanation:
Simple machine is the simplest device to use mechanical advantages. It has simplest mechanism to multiply the magnitude of force.
So, pair of tongs, seesaw and wheelbarrow are the example of simple machine because their mechanism is simplest.
Compound machine is a device that is made up of more than one simple machine.
so, sewing machine, fishing rod and reel and crane are example of compound machine because these devices shows more than one machine in it.
Thus, classification is as follows:
Simple machine: pair of tongs, seesaw and wheelbarrow
Compound machine: sewing machine, fishing rod and reel and crane.
Explanation:
Work done by winch = kinetic energy of car
∫ T ds = ½ mv²
∫ 225s ds = ½ mv²
225/2 s² = ½ mv²
225 s² = mv²
v = 15s / √m
Given s = 10 m and m = 2500 kg:
v = 15 (10) / √2500
v = 3 m/s
Once the atomic number of an atom is known, the number of electrons can be deduced depending on if the atom is an ion or a neutral one.
<h3>Atomic number</h3>
The atomic number of an atom is the number of protons in the nucleus of the atom.
For atoms that are neutral, that is, no net charges, the number of protons is always equal to the number of electrons. In other words, the positive charges always balance the negative charges in neutral atoms.
Thus, if the atomic number of a neutral atom is 6, for example, the proton number will also be 6. Since the proton must balance the electron, the number of electrons will also be 6.
More on atomic numbers can be found here; brainly.com/question/17274608
<h2>When two object P and Q are supplied with the same quantity of heat, the temperature change in P is observed to be twice that of Q. The mass of P is half that of Q. The ratio of the specific heat capacity of P to Q</h2>
Explanation:
Specific heat capacity
It is defined as amount of heat required to raise the temperature of a substance by one degree celsius .
It is given as :
Heat absorbed = mass of substance x specific heat capacity x rise in temperature
or ,
Q= m x c x t
In above question , it is given :
For Q
mass of Q = m
Temperature changed =T₂/2
Heat supplied = x
Q= mc t
or
X=m x C₁ X T₁
or, X =m x C₁ x T₂/2
or, C₁=X x 2 /m x T₂ (equation 1 )
For another quantity : P
mass of P =m/2
Temperature= T₂
Heat supplied is same that is : X
so, X= m/2 x C₂ x T₂
or, C₂=2X/m. T₂ (equation 2 )
Now taking ratio of C₂ to c₁, We have
C₂/C₁= 2X /m.T₂ /2X /m.T₂
so, C₂/C₁= 1/1
so, the ratio is 1: 1
