Explanation:
a) <em>Fixed points</em> are the temperatures at which a thermometer is calibrated. They can refer either to the actual temperatures used for calibration, or the thermometer readings at those temperatures.
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b) <em>Fundamental interval</em> is the difference between the fixed points. As with fixed points, it can refer either to the difference in actual temperature, or the difference in the corresponding thermometer readings.
PE = mgh
Mass, m = 7kg, g ≈ 10 m/s², height = 2m
= 7*10*2
= 140 Joules.
Answer:
a) 
b) 
Explanation:
Let's find the radius of the circumference first. We know that bob follows a circular path of circumference 0.94 m, it means that the perimeter is 0.94 m.
The perimeter of a circunference is:


Now, we need to find the angle of the pendulum from vertical.


Let's apply Newton's second law to find the tension.

We use centripetal acceleration here, because we have a circular motion.
The vertical equation of motion will be:
(1)
The horizontal equation of motion will be:
(2)
a) We can find T usinf the equation (1):

We can find the angular velocity (ω) from the equation (2):

b) We know that the period is T=2π/ω, therefore:

I hope it helps you!
Answer:
Both will reach to same height
Explanation:
Here we can see that friction is to be ignored
so we can say that work done by all the non conservative forces is change in mechanical energy
Since all non conservative forces here is zero
so mechanical energy is conserved here
so here we can say that sum of initial kinetic energy and potential energy = sum of final kinetic energy and potential energy
So we will have

now maximum height is given as

so here we can say that greatest height will be independent of the mass so they both will reach at same height
Answer:
He should stand from the center of laser pointed on the wall at 1.3 m.
Explanation:
Given that,
Wave length = 650 nm
Distance =10 m
Double slit separation d = 5 μm
We need to find the position of fringe
Using formula of distance



Put the value into the formula


Hence, He should stand from the center of laser pointed on the wall at 1.3 m.