Q&A - PSLE Science

[charsen]

Hi insane papa,

The readon why i convert the heat and sound and kinetic energy to gravitational potential energy is that water driped from the water wheel,which means that it has gravitational potential energy.
Anybody has a etter explanation?
Charsen

[insanePaPa]

charsen:

Hi
The answer should be
Gravitational potential energy(water in the beaker)--->kinetic energy(dripping water)--->kinetic energy+sound energy +heat energy(in the water wheel)--->gravitational potential energy(in the water)--->kinetic energy(water dripping to the dish)
Charsen.

Hi Charsen,

Thanks for your prompt reply. The answer in the answer sheet is the 2nd one mentioned in my post. Seem like there could be various possible answerd to it?

insanePaPa

[balu_priya]

Please help. This is a prelim paper which I got from a neighbour. http://i47.tinypic.com/212a2s7.jpg\">

[Blue Dolphin]

balu_priya:

Please help. This is a prelim paper which I got from a neighbour. http://i47.tinypic.com/212a2s7.jpg\">

(3) Cup T - largest surface area

[balu_priya]

Deleted.

[balu_priya]

Blue Dolphin:

balu_priya:

Please help. This is a prelim paper which I got from a neighbour. http://i47.tinypic.com/212a2s7.jpg\">

(3) Cup T - largest surface area

Why? I thoght that the round cup has larger exposed surface area. Please enlighten me.

[Blue Dolphin]

balu_priya:

Blue Dolphin:

[quote=\"balu_priya\"]Please help. This is a prelim paper which I got from a neighbour. http://i47.tinypic.com/212a2s7.jpg\">

(3) Cup T - largest surface area

Why? I thoght that the round cup has larger exposed surface area. Please enlighten me.[/quote]Recall those cupcake wrappers? Once it \"open up\", the surface area is much larger than a round cup of similar diameter.

Or perhaps to think about curtains; when the curtain is \"unfolded\", it is about 1.5 times longer.

[Robertpattinsonidle]

insanePaPa:

Pls enlighten me, pls.


A plastic beaker, with a hole at the bottom, is held above a waterwheel using a retort stand. Water dripping from the beaker causes the waterwheel to turn. Water drips into a dish place below. State the energy conversion that takes place.

Is this answer correct?
Gravitational potential energy (water in the beaker)--> Kinetic energy (waterwheel)--> Heat & Sound energy (water in the dish).

or this
Gravitational potential energy (water in the beaker)--> Kinetic energy (waterwheel)--> Potential energy (water in the dish).

:thankyou:

insanePaPa

Second one is correct. If possible add sound energy but that is not neede here in this case. Thanks
Robertpattinsonidle ft.JB

[Robertpattinsonidle]

Blue Dolphin:

Blue Dolphin:

[quote=\"balu_priya\"]Please help. This is a prelim paper which I got from a neighbour. http://i47.tinypic.com/212a2s7.jpg\">

(3) Cup T - largest surface area

Why? I thoght that the round cup has larger exposed surface area. Please enlighten me.[/quote]Recall those cupcake wrappers? Once it \"open up\", the surface area is much larger than a round cup of similar diameter.

Or perhaps to think about curtains; when the curtain is \"unfolded\", it is about 1.5 times longer.[/quote]
But the qsn did not say to open up. So anwer should be the first one. Thanks
robertpattinsonidle ft. JB

[insanePaPa]

Robertpattinsonidle:

insanePaPa:

Pls enlighten me, pls.


A plastic beaker, with a hole at the bottom, is held above a waterwheel using a retort stand. Water dripping from the beaker causes the waterwheel to turn. Water drips into a dish place below. State the energy conversion that takes place.

Is this answer correct?
Gravitational potential energy (water in the beaker)--> Kinetic energy (waterwheel)--> Heat & Sound energy (water in the dish).

or this
Gravitational potential energy (water in the beaker)--> Kinetic energy (waterwheel)--> Potential energy (water in the dish).

:thankyou:

insanePaPa

Second one is correct. If possible add sound energy but that is not neede here in this case. Thanks
Robertpattinsonidle ft.JB

Thanks Robertpattinsonidle for your input.
Is it true that if this setup is useful in a particular application (e.g. water turbine to generate electricity), then it should end with 'Potential energy'?