A wind powered generator of electricity can produce electrical energy at a rate of 5000W.
state the form of energy which is removed from the air in order to make the generator work.
why is the ans kinetic energy?
movements from the flow of air changed to turning of generator turbine
Originally posted by eagle:movements from the flow of air changed to turning of generator turbine
huh? so air got kinetic energy?
this ques how to do ar:
When a ruler is held so that it sticks out over the end of a desk, a sound wave can be produced by flickering the end of the ruler.
(a) how could the ruler be made to produce a louder sound?
(b) when the length of the ruler sticking out beyond the edge of the desk is decread, the sound produced by flickering the ruler is of a higher frequency. what simple observation confirms this statement?
Originally posted by crucifiedx:
huh? so air got kinetic energy?
ya, as long as there's movements, there's kinetic energy
Originally posted by crucifiedx:this ques how to do ar:
When a ruler is held so that it sticks out over the end of a desk, a sound wave can be produced by flickering the end of the ruler.
(a) how could the ruler be made to produce a louder sound?
(b) when the length of the ruler sticking out beyond the edge of the desk is decread, the sound produced by flickering the ruler is of a higher frequency. what simple observation confirms this statement?
(a) Louder means must larger amplitude
So flick harder
(b) higher pitch sound
a) how could the ruler be made to produce a louder sound?
i thought material?
Originally posted by crucifiedx:a) how could the ruler be made to produce a louder sound?
i thought material?
haha... no.... Doesn't mean that here...
Originally posted by eagle:haha... no.... Doesn't mean that here...
ok.. haha. i thought they asking for material. thanks. (:
What abt this ques?
Express why the filament reaches a constant teperature, even though heat is produced continually as current flows through the bulb.
Originally posted by crucifiedx:What abt this ques?
Express why the filament reaches a constant teperature, even though heat is produced continually as current flows through the bulb.
you mean why eventually, the filament reaches a constant temperature?
Because the rate of heat loss is equal to the rate of heat being produced, that's why it will be at constant temperature
My turn to pop a question lers x.x this question may seems easy but i asked 3 times and forget the explanation lers x.x
Position | Just After Throwing | At the highest point | Just before being caught
Acceleration 10ms^-2 10ms^-2 10m^-2
Speed 8m/s 0 m/s 8m/s
*-Given
Fill in the blanks =) Though i know for the acceleration the blanks are all 10ms^-2 but i forget why is it so ?Why the speed at the highest point is 0 and the one being caught is 8?Can a kind soul kindly explain please?Thanks!
Originally posted by eagle:you mean why eventually, the filament reaches a constant temperature?
Because the rate of heat loss is equal to the rate of heat being produced, that's why it will be at constant temperature
think so?
good question
acceleration is constant because it is gravitational acceleration... constant throughout the projectile motion
speed at highest is 0 because it is the turning point. Imagine, you move upwards, then slow down, then 0, then start to accelerate downwards. If it cannot reach 0, then how to turn?
speed at the end is 8 m/s as well. Note that this is speed; if it is velocity, it will be 8m/s downwards, and initial vel will be 8m/s upwards. The reason for the same speed is because of conservation of energy. At first, the k.e. gets converted to g.p.e. as it rises, till the turning point, it starts coming down. As it comes down, the g.p.e. starts changing back to k.e. At every point, k.e. + g.p.e. is a constant.
Originally posted by crucifiedx:
think so?
means?
Originally posted by jlzk:My turn to pop a question lers x.x this question may seems easy but i asked 3 times and forget the explanation lers x.x
Position | Just After Throwing | At the highest point | Just before being caught
Acceleration 10ms^-2 10ms^-2 10m^-2
Speed 8m/s 0 m/s 8m/s
*-Given
Fill in the blanks =) Though i know for the acceleration the blanks are all 10ms^-2 but i forget why is it so ?Why the speed at the highest point is 0 and the one being caught is 8?Can a kind soul kindly explain please?Thanks!
i dunno this ques too. from tys yr1999 de right?
Originally posted by crucifiedx:i dunno this ques too. from tys yr1999 de right?
heheh yupp . I asked 3 different teachers 3 times keep forget x.x hope i can remember this time. Eagle thanks! =)
Originally posted by eagle:means?
that ques is exactly from tys. i don't understand the ques also.
Originally posted by crucifiedx:i dunno this ques too. from tys yr1999 de right?
that was my O levels year lol
but I took pure physics