Solve Yr 11 Physics HW: Find Work Done & Energy Expended

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A user seeks assistance with a physics problem involving a car traveling up a slope, requiring calculations for work done and energy expended. The car's mass is given, and the user struggles with determining the weight, frictional resistance, and the component of weight along the slope. Key formulas include work (w=fs) and force (f=ma), with the correct weight calculated as 20,923 N. The discussion highlights the importance of using total force in work calculations, leading to the correct answer of 3.18 * 10^5 J. The user expresses gratitude for the clarification on the calculation method.
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Hey i need some help with this question please:

A car of mass 2.135 * 10^3 travels at a constant speed up a slope of 30 degrees a distance of 25.3m. If the frictional resistance is 0.100 of the weight of the car, find:
(a) the work done
(b) the energy expended

The answer is 3.18 * 10^5 J

The formulas we have been using are w=fs and f=ma also si units please.
 
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What is the weight of the car?
What is the frictional resistance?
what is the component of the weight of the car along the slope?
What is the total force?
 
i can figure the weight out using f=ma but i keep getiing the wrong answer no matter what i do??
 
here' s what I've done so far.
weight = 2.135*10^4 N
frictional resistance = 2.094*10^3
and i try to put this into w=fs cos theata
and i get 4.589*10^5

please help
 
Weight = 2.135*10^3*9.8 = 20923 N
The component of the weight of the car along the slope = 20923 N*sin(30 degree)
Total force = 20923 N*sin(30 degree) + 20923*0.100 N
Now find the work done.
 
hey thanks a lot for the help what i missed was that when you calculate the workdone it is the total force and not just the weight. thanks again
 

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