Sci-box_In full swing (M)

			In full swing (M)


		How is the period of a pendulum affected by the mass on the end of the string?

		Don't stand too close to the pendulum when the mass is being released.

PLAN	Set up the pendulum. ( A *pendulum* is any mass which swings back and forth on a string or chain.) Attach a mass to the bottom of the string. Release the pendulum and time 5 complete swings (back and forth is ONE complete swing). The time taken for a complete swing is called the *period* of the pendulum. You can work out the period by dividing your recorded time by 5. Change the mass by adding another item or replacing with a heavier item. Release and time 5 swings (periods). Repeat several times with different masses.			I WILL NEED	Length of string. A fixed point to support the pendulum (e.g.: a shelf). Several weights (nuts or large washers . A watch with a second hand. Pencil and paper.
				I MAY NEED	A stopwatch would be useful (but not essential).
				FAIR TEST	Does it matter how far back you pull the mass? How much string is being used to tie the weights on?

	PREDICTION	What do you think might happen? Will the larger mass travel faster and have a shorter period or will it slow down and have a longer period. Does this connect to any science you have done or heard about previously?

PRACTICAL ACTIVITY	Where did you fix your pendulum? Why did you choose this position? What was the best way to attach the mass to the string? Who did what during the investigation? Did you encounter any problems? What did you do to overcome these?			COLLECT DATA	How will you make sure that your timing is accurate?
				ANALYSE DATA	You may find it easier to analyse your data if you draw a chart or a graph.
				PRESENT FINDINGS	What is the best way to show what you did? Would a diagram make things clearer? Could you video part of the investigation? What is the best way to show your data and explain your findings?

	EVALUATE INVESTIGATION	Were you pleased with this investigation? If not, which part of it could have been conducted differently?

	If you have carried out this investigation, click the icon to send in your results to Brainboxx and we may publish your work on the website. It is best to e-mail the results of your investigation or you may need to send them by post. Make sure you get permission from a teacher, parent or other adult before you get in touch.
	Pendulum		Changing mass		Moon pendulum