Q&A - P3 Science

[Lynn2]

Thanks, Tianzhu.


Hey Folks

I have more questions to ask...help.

1Which of the following statement is /are false?
A The temperature of an object tells us how cold or hot an object is.
b The temperature of an object is a measure of the amount of heat of the object has.
c Glass is used to make a clinical thermometer because it is a good conductor of heat.

Answer is B and c only.But my girl think its A only as she thinks that glass is a bad conductor of heat.

May I know what is your answer?

2 Mrs Smith puts a kettle of water to boil.A steel sheet,clamped to a retort stand is placed directly above the opening of the mouth of the kettle.A heating element is used to maintain the temperature of the steel sheet at 100 deg celsius.

When the water started to boil, which of the following statements correctly describe what would happen?
1 The steel sheet expanded.
2Tiny water droplets could be seen on the underside of the steel sheet,

Answer is 1 Just wonder why is it not 2?

20 A few spoonfuls of salt were added into the beaker of crushed ice.Which one of the following graph correctly shows how the readings of thermometers p and W change when the salt was added?

Sorri, cant scan the graph cos no scanner.May i just write it down.

Answer : Temperature of p drop as mins go on,temperature of q, drop from zero to freezing point and go up but still below zeros degree.

Can someone explain how the salt affect the water level and temperature ?thanks everyone...

Cheers

tianzhu:

Hi

Based on the concept that a transparent object will not make any shadow, as light will pass straight through it, only a triangle can be seen.

[Lynn2]

Hello all, am trying to work out some MCQ with my gal, can cross check on …


1 We can clearly feel our heartbeat at our…

ans : wrists,temples and neck.

May I know why temples is one of the point?

2 What will happen if we have a weak heart?

thanks

[tianzhu]

[quote]1Which of the following statement is /are false?

A The temperature of an object tells us how cold or hot an object is.
b The temperature of an object is a measure of the amount of heat of the object has.
c Glass is used to make a clinical thermometer because it is a good conductor of heat.[/quote]
Hi
Heat is a form of energy that makes an object hot.It is a measure of the amount of heat of the object has.

Glass is used in clinical thermometers because it is transparent. Temperature readings can be taken off quickly and easily from the thermometer.

The question asked for statements which are false. Hence option (b) and (c) are logical.

[tianzhu]

[quote]2 Mrs Smith puts a kettle of water to boil.A steel sheet,clamped to a retort stand is placed directly above the opening of the mouth of the kettle.A heating element is used to maintain the temperature of the steel sheet at 100 deg celsius.


When the water started to boil, which of the following statements correctly describe what would happen?
1 The steel sheet expanded.
2Tiny water droplets could be seen on the underside of the steel sheet,[/quote]
Hi
The key point is A heating element is used to maintain the temperature of the steel sheet at 100 deg celsius.

Condensation takes place when steam touches a cooler surface. Therefore option (1) is correct.

[tianzhu]

[quote]A few spoonfuls of salt were added into the beaker of crushed ice.Which one of the following graph correctly shows how the readings of thermometers p and W change when the salt was added?


Sorri, cant scan the graph cos no scanner.May i just write it down.

Answer : Temperature of p drop as mins go on,temperature of q, drop from zero to freezing point and go up but still below zeros degree.[/quote]
Hi
Where are the positions of thermometers P and W? What is temperature q?
Without scanner, you may try to take a picture of the question using a digital camera and insert as an image.

[tianzhu]

Lynn2:

Hello all, am trying to work out some MCQ with my gal, can cross check on ....


1 We can clearly feel our heartbeat at our....

ans : wrists,temples and neck.

May I know why temples is one of the point?

2 What will happen if we have a weak heart?

thanks

Hi
May I suggest you post the complete questions showing all options for these MCQ questions. Sometimes. we can use elimination process to weed out options that are obviously offside.

[Lynn2]

Hi Tianzhu


Thanks

Here is the full question.

We can clearly feel our heartbeat at our____
a wrists b temples
c neck d forehead

1 a and c 2 b and d only
3 a b and c only 4 a,b,c and d

tianzhu:

Lynn2:

Hello all, am trying to work out some MCQ with my gal, can cross check on ....

1 We can clearly feel our heartbeat at our....

ans : wrists,temples and neck.

May I know why temples is one of the point?

2 What will happen if we have a weak heart?

thanks

Hi
May I suggest you post the complete questions showing all options for these MCQ questions. Sometimes. we can use elimination process to weed out options that are obviously offside.

[Lynn2]

Thanks for the great suggestions.I will use my digital cam take the questions and post up later


cheers

tianzhu:

[quote]A few spoonfuls of salt were added into the beaker of crushed ice.Which one of the following graph correctly shows how the readings of thermometers p and W change when the salt was added?

Sorri, cant scan the graph cos no scanner.May i just write it down.

Answer : Temperature of p drop as mins go on,temperature of q, drop from zero to freezing point and go up but still below zeros degree.

Hi
Where are the positions of thermometers P and W? What is temperature q?
Without scanner, you may try to take a picture of the question using a digital camera and insert as an image.[/quote]

[Lynn2]

Hi Tianzhu


Finally able to play with the gadget and here is the questions as below:

tianzhu:

[quote]A few spoonfuls of salt were added into the beaker of crushed ice.Which one of the following graph correctly shows how the readings of thermometers p and W change when the salt was added?

Sorri, cant scan the graph cos no scanner.May i just write it down.

Answer : Temperature of p drop as mins go on,temperature of q, drop from zero to freezing point and go up but still below zeros degree.

Hi
Where are the positions of thermometers P and W? What is temperature q?
Without scanner, you may try to take a picture of the question using a digital camera and insert as an image.[/quote]http://www.postimage.org/image.php?v=aV1Sz9L9

[tianzhu]

Hi


I think there are two ways to take heart rates.

1)place your hand on the pulse of your wrist
2)place your fingers on the side of the Adam’s apple on your neck until you find the pulse.

You may refer to this site for my information.
http://www.nemahealth.org/programs/healthcare/heart_rate_pulse.htm#2

A good site to find out more about our heart.
http://www.myheart.org.sg/?page_id=38

I suggest that you check with the science teacher for the correct answer.