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The big question: How strong is our sun? Why are we learning this? The sun is dying, slowly…. Homework: P139 q1. Learning Objective: To combine knowledge on speed, power output and intensity The big question: How strong is our sun? A – Evaluate efficiency, power and intensity - PowerPoint PPT Presentation
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The big question:How strong is our sun?
Why are we learning this?
The sun is dying,slowly…
Homework:
P139 q1
Learning Objective: To combine knowledge on speed, power output and intensity
The big question:How strong is our sun?
A – Evaluate efficiency, power and intensityB – Predict sound intensity and predict reasons for inaccuracyC – Calculate the sun’s power for different planetsD – Identify intensity/amplitude relationship
Plot 2 waves on displacement-time graphs,one with amplitude TWICE the size of the other, but both in phase
Speed = gradient of a wave. At displacement 0, draw on the gradients
(C) Plot a wavewith halfthe gradient ofthe smaller one
Plot 2 waves on displacement-time graphs,one with amplitude TWICE the size of the other, but both in phase
Speed = gradient of a wave. At displacement 0, draw on the gradients
If 1 gradientis twice the other,one speed is twice
KE= ½ mv2
Learning Objective: To combine knowledge on speed, power output and intensity
The big question:How strong is our sun?
A – Evaluate efficiency, power and intensityB – Predict sound intensity and predict reasons for inaccuracyC – Calculate the sun’s power for different planetsD – Identify intensity/amplitude relationship
For your task you need to provide:
- AN EXPLANATION- A SHEET OF WRITING YOU CAN GIVE TO THE OTHER GROUP- 3 QUICK NUMERICAL QUESTIONS FOR THEM, WITH ANSWERS- KEY PHRASES (WORDS+MEANINGS)
On whiteboards again…
The sun’s power output is 3.7 x 1023 kWIts distance to earth is 1.5x1011 m
Neptune is 30 times further from the sun than earth.
Calculate what the power output to Neptune is
Learning Objective: To combine knowledge on speed, power output and intensity
The big question:How strong is our sun?
A – Evaluate efficiency, power and intensityB – Predict sound intensity and predict reasons for inaccuracyC – Calculate the sun’s power for different planetsD – Identify intensity/amplitude relationship
Pick a question, and complete in pairs..
(B) P144 q4
(A) P144 q5
He said she said…
Mr Singh (B) says “Minimum energy to blow a car window is 0.5W. A 10W circular subwoofer 1m away from the back-window would be safe”
Mrs Brown (A) says “If minimum energy necessary to keep earth alive is 1012W,and the sun loses 50% of its 3.7 x 1023 kW power, we could be 100m away and still die”
Are they correct? Why?
Learning Objective: To apply use of wave analysis
The big question:How can we analyse a wave?
A – Predict values using wave termsB – Evaluate consistency across wave termsC – Calculate wave terms for a variety of wavesD – Understand the 6 key wave terms