Four persons K , L , M , and N are initially at the four corners of a square of side 'd ' . Each person now moves with a uniform speed of ` v ' in such a way that K always moves directly towards L , L directly towards M , M directly towards N and N directly towards K . At what time will the four persons meet ?
A truck is moving 60 mph , I throw a ball when inside the truck at 60 mph in the opposite direction of the vehicle 's motion . How would the ball travel ?