Does the scalar of Weight (W) = mg all the time?

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SUMMARY

The weight of an object, such as a penguin in a sled, is consistently defined by the equation W = mg, where W represents weight, m is mass, and g is the acceleration due to gravity (9.8 m/s²). Regardless of the incline angle, the weight remains constant at 80N for the penguin. To find the mass, one divides the weight by 9.8, yielding m = W/9.8. The force of gravity acting along the incline can be calculated using the formula mgsin(theta), but the weight itself is not affected by the angle of the incline.

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I have a question in my textbook where I'm given weight of a "penguin in a sled" as 80N but the object is on a 40 degree angle. Is it telling me that on a normal flat surface the weight is 80N so that way to figure out the force of gravity on the x-axis I must divide the W by 9.8 then plug in my m (mass) that I get to find for the force of gravity along the x-axis as: mgsin(theta)? In the solution that a user posted on slader, they said to find mass its W/9.8 even though the object is being used on a incline of 40 degrees?
 
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NYGooner said:
I have a question in my textbook where I'm given weight of a "penguin in a sled" as 80N but the object is on a 40 degree angle. Is it telling me that on a normal flat surface the weight is 80N so that way to figure out the force of gravity on the x-axis I must divide the W by 9.8 then plug in my m (mass) that I get to find for the force of gravity along the x-axis as: mgsin(theta)? In the solution that a user posted on slader, they said to find mass its W/9.8 even though the object is being used on a incline of 40 degrees?
Doesn't matter what the angle of incline is. The penguin could be climbing up the side of a cliff (angle to the horizontal = 90°), and W = mg for the penguin.

Think about what is going on. The weight of the penguin (or any object) is produced by the object's attraction to the earth, not some random object nearby. As such, the force vector which we call an object's weight, will have a certain direction, which doesn't change:

free-body-force-diagram-block-on-frictionless-incline.png
Although the weight of an object doesn't change, the same can't be said for any contact forces between the object and an inclined surface, for instance, as you can see in the diagram above.
 
Just to add: A weight is a force and thus never a scalar!
 

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