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17. A volleyball weighs about 300 grams.

Calculate the potential energy of a volleyball
that is in the air at a height of 15 m. (g = 9.8
m/s-). Round your answer to two decimals
and show the correct units of measure. Be
sure to convert units if necessary.

User Greuze
by
4.1k points

1 Answer

5 votes

Answer:

PE = 44.1 J

Step-by-step explanation:

Ok, to have the specific data, the first thing we must do is convert from grams to kilograms. Since mass must always be in kilograms (kg)

We have:

  • 1 kilograms = 1000 grams.

We convert it using a rule of 3, replacing, simplifying units and solving:


  • \boxed{\bold{x=(gr*1\ kg)/(1000\ gr)=(300\ gr*1\ kg)/(1000\ gr)=(300\ kg)/(1000)=\boxed{\bold{0.3\ kg}}}}

==================================================================

Earth's gravity is known to be 9.8 m/s², so we have:

Data:

  • m = 0.3 kg
  • g = 9.8 m/s²
  • h = 15 m
  • PE = ?

Use formula of potencial energy:


  • \boxed{\bold{PE=m*g*h}}

Replace and solve:


  • \boxed{\bold{PE=0.3\ kg*9.8(m)/(s^(2))*15\ m}}

  • \boxed{\boxed{\bold{PE=44.1\ J}}}

Since the decimal number, that is, the number after the comma is less than 5, it cannot be rounded, then we have this result.

The potential energy of the volleyball is 44.1 Joules.

Greetings.

User Kolors
by
5.3k points