Answer:
K.E₂ = mg(h - 2R)
Explanation:
The diagram of the car at the top of the loop is given below. Considering the initial position of the car and the final position as the top of the loop. We apply law of conservation of energy:
K.E₁ + P.E₁ = K.E₂ + P.E₂
where,
K.E₁ = Initial Kinetic Energy = (1/2)mv² = (1/2)m(0 m/s)² = 0 (car initially at rest)
P.E₁ = Initial Potential Energy = mgh
K.E₂ = Final Kinetic Energy at the top of the loop = ?
P.E₂ = Final Potential Energy = mg(2R) (since, the height at top of loop is 2R)
Therefore,
0 + mgh = K.E₂ + mg(2R)
<u>K.E₂ = mg(h - 2R)</u>
Is there a multiple choice?
Answer:
They are the simplest mechanisms known that can use leverage (or mechanical advantage) to increase force. The simple machines are the inclined plane, lever, wedge, wheel and axle, pulley, and screw. simple machines.
Complete Question
The complete question is shown on the first uploaded image
Answer:
The uncertainty in inverse frequency is ![\Delta [\frac{1}{w} ]= \frac{3}{2000} \ s](https://tex.z-dn.net/?f=%5CDelta%20%20%5B%5Cfrac%7B1%7D%7Bw%7D%20%5D%3D%20%20%5Cfrac%7B3%7D%7B2000%7D%20%5C%20s)
Explanation:
From the question we are told that
The value of the proportionality constant is 
The strength of the magnetic field is 
The change in this strength of magnetic field is 
The magnetic field is given as
Where 
is frequency
The uncertainty or error of the field is given as
![\Delta B = \frac{k }{[\frac{1}{w}^]^2 } \Delta [\frac{1}{w} ]](https://tex.z-dn.net/?f=%5CDelta%20%20B%20%20%3D%20%20%5Cfrac%7Bk%20%7D%7B%5B%5Cfrac%7B1%7D%7Bw%7D%5E%5D%5E2%20%7D%20%20%5CDelta%20%5B%5Cfrac%7B1%7D%7Bw%7D%20%5D)
The uncertainty in inverse frequency is given as
![\Delta [\frac{1}{w} ] = \frac{\Delta B}{k [\frac{1}{w^2} ]}](https://tex.z-dn.net/?f=%5CDelta%20%20%5B%5Cfrac%7B1%7D%7Bw%7D%20%5D%20%20%3D%20%5Cfrac%7B%5CDelta%20B%7D%7Bk%20%5B%5Cfrac%7B1%7D%7Bw%5E2%7D%20%5D%7D)
![\Delta [\frac{1}{w} ]= \frac{\Delta B}{k (B)^2 }](https://tex.z-dn.net/?f=%5CDelta%20%20%5B%5Cfrac%7B1%7D%7Bw%7D%20%5D%3D%20%20%5Cfrac%7B%5CDelta%20B%7D%7Bk%20%28B%29%5E2%20%7D)
substituting values
![\Delta [\frac{1}{w} ]= \frac{3}{5 (20)^2 }](https://tex.z-dn.net/?f=%5CDelta%20%20%5B%5Cfrac%7B1%7D%7Bw%7D%20%5D%3D%20%20%5Cfrac%7B3%7D%7B5%20%2820%29%5E2%20%7D)
Answer:
Current in the hair dryer will be equal to 15 A
Explanation:
We have given that household is operated at 110 volt
So potential difference V =110 volt
Power drawn by hairdryer is P = 1650 watt
We have to find the current in the hair dryer
We know that power is given as P = VI, here V is potential difference and I is current
So 
I = 15 A
So current in the hair dryer will be equal to 15 A
