 Let's talk about right angles and straight angles. This will also help us understand the directions and sentences where these two terms are used in math. So for example, the right angle is of 90 degrees. So if I say I'm looking towards this direction here, which is east, I'll just quickly draw the direction map east, west, south at the bottom and the north at the top. So I'm looking towards east and if I turn anticlockwise by 90 degrees, I have eyes towards north. So these are eyes. So this is how I turn and look at north. So I would say I have turned anticlockwise by 90 degrees or through a right angle. Similarly, what happens if I turn myself by a straight angle? Straight angle is of 180 degrees. So I'm turning completely by 180 degrees and if I have eyes now towards west, so I have turned anticlockwise in a straight angle and I would look at west and through a diagram, this is the angle that I've turned in. So right angle is a 90 degree angle and a straight angle is a 180 degree angle. But when do we find applications of terminologies like right angles or straight angles? So when we have to describe the directions through which objects are moved, for example, let's take example of a clock and I'll draw 12, 3 here, 6 at the bottom and 9 towards left and let's draw only one hand because we are just interested in the rotation of one hand. So let's say a minute hand is at 3. When this moves to 9, it completes one half a rotation about the clock and it has turned in 180 degrees. So we would say that the minute hand has turned clockwise in a straight angle. So this has completed one straight angle. What happens if it rotates completely and again comes back to 3? It completes two 180 degree rotations in that case and that would mean it will be completing two straight angle rotations clockwise. What if the minute hand was at 6 and then it rotated three-fourth straight angle? And we already know that the clock hand is going to move clockwise. So we go about this, three-fourth of 180 degrees is what we need and that is going to be 135 degrees. That's basically completing 190 degree rotation and then completing a half 90 degree rotation. This is 90 degrees and this is 45 degrees and that makes up 35 degrees and then you would say this is three-fourth of a straight angle or three-fourth of 180 degrees rotation. You can count the number of right angles moved or straight angles moved when a minute hand of the clock or the hour hand of a clock moves for any time duration. So there is this question in 24 hours, how many straight and right angles are moved by the minute hand? Note that for every 15 minutes, it will complete the movement of 90 degrees. So use this information and try and answer this question. Pause this video to solve this question before I share the answer on the screen. So in 24 hours, there are 24 full rotations and we know that one full rotation is worth two straight angles. So 48 straight angles are moved by the minute hand and since one straight angle include two right angles, 96 right angles, 96 right angles were moved from the original position by the minute hand in 24 hours.