Question

1. You take a cylinder of metal and place it inside a cup containing enough boiling water to cover the metal. Describe what happens to the metal and the water in terms of heat energy, particles and temperature.

2. You have a parallel circuit with two resistors, both 50Ω, connected in parallel to a battery of 9V. You note the total current to be 0.36A. Now, You now add a third resistor in another, third parallel branch, also 50Ω. Describe what happens to the total resistance and total current in the circuit compared to before. (There is no need for any calculations here, but you are welcome to. Just make sure you answer the question with words, and the numbers provided can be used for reference).

3.

You are using a pendulum in the lab, in order to measure the value of 'g', the acceleration due to gravity near Earth's surface. It is known that the accepted value is g = 9.81m/s². You calculate a value in the lab of g = 10.08m/s². Which type of error should you calculate, percent difference or percent error, and why?

Also, calculate the one you choose and type it into your answer, rounding it to two decimal places.

Answer 1

1. Heat energy of boiling water will reduce and that of metal cylinder will increase. Separation among the particles of water will reduce and that among the particles of metal cylinder will increase. Temperature of water will reduce and that of metal cylinder will increase.

2. As in parallel combination, net resistance is given by the inverse of sum of inverses of varoiuos resistance, so net resistance is reduced hence net current coming out of the battery is increased.

3. Percent difference = {(10.08 - 9.81)/9.81}100 = 2.75%