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3 years ago

What dose it mean to say that mass is conserved during a physical change

Physics

2 answers:

xxMikexx [17]3 years ago

8 0

Answer:

When a physical change occurs, the mass of the substance is conserved. This means that the total mass of the substance remains the same from beginning to end. The physical properties of the substance, such as size and shape, may change, but the amount of matter in the substance does not change.

Explanation:

Allushta [10]3 years ago

6 0

Explanation:

When there is no change in chemical composition of a substance then it is known as physical change.

When we say that mass is conserved during a physical change then it means that total mass of the substance or object will remain the same from beginning till the end.

For example, a metal box of mass 20 grams is beaten with hammer. Its shape will change which is a physical change and after beaten with the hammer its mass still remains 20 grams.

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Answer:

(a) %a, 10 A, 0.833 A

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Explanation:

Power of toaster, P1 = 600 W

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V = 120 V

As they are in household circuit, so they are connected in parallel, so the voltage is same for all.

(a) Use the formula P = V x i

Current in toaster, i1 = P1 / V = 600 / 120 = 5 A

Current in iron, i2 = P2 / V = 1200 / 120 = 10 A

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(b) Resistance of heating element of iron is R2.

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3 years ago

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Answer:

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Explanation:

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Answer:

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Explanation:

The problem relates to variation of weight due to change in height .

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3 years ago

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sleet_krkn [62]

Answer:

T=280.41 °C

Explanation:

Given that

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