Wednesday, April 30, 2014

RC - Circuit

In RC-Circuit,there are a battery,a capacitance,and a resistor. When the circuit is close access, the capacitance begins to store charge. When the circuit takes out the battery, and forms close access, the capacitance is instead of battery to release charge. In this activity, the lab is instead of resistor. When we turn on the the battery, the lab is from bright to turn off because charge store in the capacitance.
When we used two capacitance in the circuit, and the two capacitance were series, the lab would turn off later than the fist activity because the series capacitance make the total capacitance become small. The capacitance became small, so it stored less charge than the fist activity,and the lab could bright longer than the fist activity.
When the two capacitance were parallel, the lab would turn off faster because the parallel capacitance made the total capacitance become large. It could store more charge.

 This picture showed the capacitance was charge in RC-Circuit.

This picture showed the capacitance was discharge in RC-Circuit.
This graph showed the voltage of capacitance vs. time in charge of RC-Circuit and discharge of RC-Circuit.
Therefore the Voltage have a relationship with the capacitance and resistor

The last picture showed the current and voltage of capacitance vs. time, and the current and voltage of resistor vs. time. 

Wednesday, April 23, 2014

Capacitance

We cut two same area raps, and put them to inside of the book. The two raps is set in different pages, then we calculated the capacitance in the different distance of two raps at 1 cm, 10 cm, and 20 cm. Next, we used the half areas of the two raps, and we calculated the capacitance in different distance of two raps at 1 cm, 10 cm, and 20 cm.

From the data and graph, we knew that the capacitance has relationship with the area of plate and the distance of the two plates.
Calculating the sum of the capacitance in series and parallel

Monday, April 14, 2014

Power and Work


This activity showed that the temperature can affect the work and the power. When the temperature rose, the power and the work followed increase.
The hot dog activity
This picture showed the work of a cylinder in the electric fired. Different angles of cylinder had different work.

Wednesday, April 9, 2014

Current, Voltage, Resistance, and Power

In this question, we selected mode D

This activity showed measuring of current of resistance and voltmeter and voltage of battery, then, calculating the power of resistance and the power of voltmeter.

This picture showed the data and graph for measuring numbers and calculating numbers. From the graph, we knew that current, voltage, and power have relationship. They are direct ratio.
The resistance has relationship with density, length, and area. From the formula, we knew that the length and density is big, and the area is small, so the resistance is big.
This data showed different material,length, and area have different resistance.