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# Help Zone

## Discussion List

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Secondary IV • 2yr.

Why do we sometimes calculate the work with the cosinus of the angle between the force and the displacement and sometimes without it? Is this in a special case or an exception?

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Secondary IV • 2yr.

The Perseverance robot weighs 1025 kg on Earth. What will be its weight on Mars? Can you help me?

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Secondary IV • 2yr.

Why do we sometimes calculate the work with the cos of the angle between the force and the displacement and sometimes without? Is this in a special case or an exception?

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Secondary IV • 2yr.

Hi! In a problem, I am told that the work done on an object is 250 J and that it moves 7.5 m by a force with an orientation of 45 °. How do I know the value of the force from this?

Thank you !

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Secondary IV • 2yr.

Hi! Why does changing tires help grip? Thanks

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Secondary IV • 2yr.

Hi! What is a lubricant used for in a mechanism? Can you give me an example? Thank youuu

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Secondary V • 2yr.

What is the difference between weight and mass? Thank you for helping me; I do not understand!!

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Secondary V • 2yr.

How is the phenomenon of dispersion explained?

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Secondary V • 2yr.

Hi!

How come when I have writing on my sweater and I look at myself in the mirror, I see the writing backwards?

Thank you for your time: D

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Secondary V • 2yr.

Hi! Could someone explain to me how white light can scatter in full color when it passes through a prism?

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Secondary V • 2yr.

Hi! I’m confusing refraction and reflection. When I look at myself in a mirror, which of the two concepts is it? And what about when I see my straw strangely when it's in my glass of water? Thank you for your help!

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Secondary IV • 2yr.

What is the difference between friction and grip?

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Secondary V • 2yr.

How do you distinguish different types of forces (I am in the ATS program)?

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Secondary V • 2yr.

Hello, can you explain to me the difference between the resultant and the balancing force ?? Thank you :))

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Secondary V • 2yr.

What is the difference between potential energy and kinetic energy?

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Secondary V • 2yr.

Why can't we create energy? How do power plants work if they don't create electricity?

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Secondary V • 2yr.

I do not understand what work is in physics?

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Secondary IV • 2yr.

How do we go from m/s to km/h and vice versa? Also, how do you convert velocities using position and time measurements?

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Secondary IV • 2yr.

Hello! In my assignment, I have to find the displacement in meters of a car if it has driven at 1.5 m / s for 30 seconds. What should I do?

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Secondary IV • 2yr.

Hello !

In physics, what is the difference between a closed system and an isolated system?

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Secondary IV • 2yr.

Good morning!

I have a science lab this week and I don't understand why in the protocol it says to weigh the weighing scoop first by itself and after the weighing scoop plus the solution.

Can someone explain to me please?

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Secondary IV • 2yr.

I do not understand the concept of effective force? Why would a force be ineffective?