 #1
 51
 0
hi there,
i am from France, so excuse my mistakes languagewise, please.
We got some longtime tasks in physics because our teacher is away. One of them is really hard. I hope you can help me a little bit.
Match the following graph to one of these experiments.
Since the graph is very small and you can not see it on computer really well, i have wrote the lookup table of the graph.
exp1: The collision of a small ball on a planar table which is located 20 cm over the ground.
y is the height of the ball in cm and x is the time after the collision in ms.
exp2: A capacitor with the capacity of 6.8 μF is charged with a resistance of 3.3 MΩ. At the beginning he has a voltage of 20V. y is the voltage in V and x is the time in s.
exp3: 100 ml water are heated electrically with the power of 350 W. The water has the temperature of 20°C at the beginning. y is the temperature in °C and x the time in s.
Ok now my ideas:
exp1: The ball is small and has a low velocity so that we can neglect the air resistance. Then the formula is h(t)= 0.2m + v*t + 1/2*g*t^2, and v is the start velocity of translation in the direction of y. We can determine v from the table: v≈ 7 m/s. I have calculated some values but after 80 ms they differ a lot from the ones of the table. So i thaught that exp1 is wrong.
exp2: The formula is U(t)= 20V+(U20V)*(1e^(t/(R*C))) with U as maximal voltage. The slope in the start point would be U´(0)= 1/(R*C)*(U20V)≈ 0.7 V/s. The value 0.7 V/s was determined with the table. But than U would be lower than 40V which is wrong.
exp3: My strategy is to use the energys:
Q= m*c*ΔT= 350W*t. However T(t) is a linear function then which differs from the values.
Consequently every experiment would be false but our teacher said that one of them is wright!
THANK YOU in advance
i am from France, so excuse my mistakes languagewise, please.
We got some longtime tasks in physics because our teacher is away. One of them is really hard. I hope you can help me a little bit.
Match the following graph to one of these experiments.
Since the graph is very small and you can not see it on computer really well, i have wrote the lookup table of the graph.
exp1: The collision of a small ball on a planar table which is located 20 cm over the ground.
y is the height of the ball in cm and x is the time after the collision in ms.
exp2: A capacitor with the capacity of 6.8 μF is charged with a resistance of 3.3 MΩ. At the beginning he has a voltage of 20V. y is the voltage in V and x is the time in s.
exp3: 100 ml water are heated electrically with the power of 350 W. The water has the temperature of 20°C at the beginning. y is the temperature in °C and x the time in s.
Ok now my ideas:
exp1: The ball is small and has a low velocity so that we can neglect the air resistance. Then the formula is h(t)= 0.2m + v*t + 1/2*g*t^2, and v is the start velocity of translation in the direction of y. We can determine v from the table: v≈ 7 m/s. I have calculated some values but after 80 ms they differ a lot from the ones of the table. So i thaught that exp1 is wrong.
exp2: The formula is U(t)= 20V+(U20V)*(1e^(t/(R*C))) with U as maximal voltage. The slope in the start point would be U´(0)= 1/(R*C)*(U20V)≈ 0.7 V/s. The value 0.7 V/s was determined with the table. But than U would be lower than 40V which is wrong.
exp3: My strategy is to use the energys:
Q= m*c*ΔT= 350W*t. However T(t) is a linear function then which differs from the values.
Consequently every experiment would be false but our teacher said that one of them is wright!
THANK YOU in advance
Attachments

13.1 KB Views: 111