Q.11.Suppose the two photographs, shown in fig. 13.1 and fig. 13.2 of NCERT had been taken at an interval of 10 seconds. If a distance of 100 metres is shown by 1 cm in these photographs, calculate the speed of the blue car.
Name two effects produced by electric current. Heating effect. Magnetic effect.
First, measure the distance covered by the blue car with the help of a scale and then proceed as given below. Suppose the distance measured by scale is 2 cm. Multiply 2 with 100 to get the actual distance = 2 × 100 = 200 m. (1cm = 100m) Interval time between the photos taken = 10 s Speed of the blue car = 20010ms=20ms
