Angles Formed by Vector î + ĵ + √2k̂

Yodaa
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Homework Statement


the angles which[/B] î + ĵ + √2k̂ makes with x axis, y-axis and z axis are?

The Attempt at a Solution


the question is basically asking us what angle î + ĵ + √2k̂ makes with î + ĵ + k̂ right?
So since √2 is just the magnitude i thought the answer would be 90, 90, 90
the answer given is 60, 60 and 45

PS: i just started learning vectors
 
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î + ĵ + √2k̂ is a vector made up of three components, but it corresponds to a single vector. From my interpretation of the question, I would assume the question expects three answers (which is seems like it does). Rather than finding the angle î + ĵ + √2k̂ makes with î + ĵ + k̂ you are finding:
a). The angle î + ĵ + √2k̂ makes with î
b). The angle î + ĵ + √2k̂ makes with ĵ
c). The angle î + ĵ + √2k̂ makes with
 
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Yodaa said:

Homework Statement


the angles which[/B] î + ĵ + √2k̂ makes with x axis, y-axis and z axis are?

The Attempt at a Solution


the question is basically asking us what angle î + ĵ + √2k̂ makes with î + ĵ + k̂ right?
So since √2 is just the magnitude i thought the answer would be 90, 90, 90
the answer given is 60, 60 and 45

PS: i just started learning vectors
##\sqrt{2}## is the coefficient of the unit vector k.

To calculate the magnitude of the vector ##i + j + \sqrt{2} k##, you still have to do some further calculations.

What you are looking for are the direction cosines of this vector:

https://en.wikipedia.org/wiki/Direction_cosine
 
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oh i had completely misinterpreted the question! Thanks for the help @Yosty22
 
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I got the answer after reading up about direction cosines! Thanks for the help @SteamKing
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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