Density of 1938 Nickel - Calculate Now!

[n77ler]

Homework Statement

A 1938-nickel has a diameter of 2.11×10-2 m, a thickness of 1.95×10-3 m, and weighs 4.94×10-2 N.
What is its density?

Homework Equations

density=m/v ? or density =w/vg

The Attempt at a Solution

cant find the volume, I feel like I should drop out of university it's the simplest problem and I'm completely stuck.

v= pir^2 ?

 

[Kurdt]

The nickel is circular so the area of the circle is $A=\pi r^2$, which you will multiply by the thickness to get the volume.

 

[Moetasim]

As a scientist, it is important to remember that everyone, including scientists, can struggle with certain concepts or problems. It is important to not be too hard on yourself and to seek help when needed. In this case, the density of an object can be calculated by dividing its mass by its volume. The volume of a cylinder, such as a nickel, can be calculated using the formula V=πr^2h, where r is the radius and h is the height/thickness. So, in this case, the volume of the nickel would be V=π(2.11×10-2 m)^2(1.95×10-3 m)=1.38×10-6 m^3. Then, using the formula density=m/V, we can calculate the density of the 1938 nickel as 4.94×10-2 N/1.38×10-6 m^3=3.58×10^4 kg/m^3. It is always important to double check your units and make sure they are consistent. I hope this helps, and don't be discouraged, we all have moments of struggle.