This usually isnt a problem but just Material 2 is very under-documented atm so im having trouble making all images the same size but properly resize with window change
Just add this style reference in your code. If you want to apply this styles to all your cards in the view, add to your style file:
mat-card img{
object-fit: cover; /*this makes the image in src fit to the size specified below*/
width: 100%; /* Here you can use wherever you want to specify the width and also the height of the */
height: 80%;
}
Another solution to this issue may be using the class of bootstrap "img-responsive". Here is a brief description