Question

question in attachment...​

Answer 1

Correct answer:

254.6N

Explanation:

The normal force is always perpendicular to the surface upon which the object is moving, and is pointed away from said surface. That means we are looking for the value for Z in the diagram.

Observe that Z and Y are equal, but opposite forces.

Z=−Y

Y=−Z

If we can solve for Y, then we can find Z.

We can use our understanding of trigonometry to find an equation for Y.

cos(θ)=adjacenthypotenuse

If we plug in a for the angle, we see:

cos(a)=YW

Since we are solving for Y, we can multiply both sides by W.

W∗cos(a)=Y

Now that we know an equation for Y, we can return to our original equation to solve for Z.

Y=−Z

Z=−(W∗cos(a))

From here, we can use Newton's second law to find the value of W, the total force of gravity.

W=mg

Substitute this into our equation for Z.

Z=−(mg∗cos(a))

Now we can solve for Z using the values given in the question for the angle, mass, and gravity.

Z=−(30kg∗−9.8ms2∗cos(30∘))

Z=−(−254.6N)

Z=254.6N