Figure shows four sets of measurements on boards A, B, C and D each of which represent a rifle target. Frank ICSE Solutions for Class 9 Physics – Measurement PAGE NO: 15 Solution 1: Measurement is an act or the result of comparison of a quantity whose magnitude is unknown with a predefined standard. Solution 24: Conditions for a beam balance to be true are. The error due to this is known as backlash error. Mass is always constant for a given body. Then the reading on the scale corresponding to the other end of the object will give the length of the object. Experiments which are the key to the development of physical theories involve, No measurement is exact. Fill the graduated cylinder with the liquid. Solution 27: A physical balance works on the principle of moments. It is avoided by turning the screw always in the same direction. Solution 21: If the zero of the circular scale lies above the line of graduation then it is called negative zero error. The weights should not be carried with bare hands to avoid the change in weights due to moisture and dust particles from the surrounding. For the same variation of voltage, voltmeter A gives a bigger deflection than voltmeter B. There are many way in which instruments can be classified. Which meter is the most sensitive?Answer: A Meter A has the smallest minimum scale division out of the four meters. screw gauge. If the zero of the circular scale remains below the line of graduation then it is called positive zero error, If the zero of the circular scale lies above the line of graduation then it is called negative zero error, A linear scale called the main scale graduated in half millimeters. The weights should be placed into weight box after use. Solution 40: The units which can neither be derived from one another, nor can they be further resolved into other units are known as fundamental units. is the activity of obtaining and comparing physical quantities of real-world objects and events. Solution 12: Vernier caliper is an instrument used for measuring small lengths of solid objects where an ordinary scale cannot be applied. Solution 7: Two types of error in a measurement are. It is distance between two consecutive threads of the screw. Solution 28: 1 light year = 9.46 x 1015 m. Solution 31: Yes, the vibration is same as the oscillation. Example 4. Solution: Instrument X is more consistent. Solution 2: Maximum possible error is 0.1 cm. Solution 6: SI unit of electric current is Ampere (A). Very small or large size may cause inconvenience. Solution: Scale B is more suitable for measuring a whole chicken because the mass of the chicken is out of the range of measurement of scale A. I like this blog. PAGE NO: 28 Solution 1: When one complete rotation is given to the screw hand, it moves forward or backward by a distance is called pitch of the screw. Consider a target as in Figure. that give a ready measure of the quantities with the help of graduated scales. Solution 38: The maintenance of standard units is essential because any variation in these standards would lead to wrong measurements, misleading results and confusing generalizations. The error due to this is known as backlash error. thus this length can be measured with an instrument of least count of 0.001 cm i.e. Solution 5: One standard kilogram is equal to the mass of a cylinder of nearly same height and diameter and made up of platinum and iridium alloy. Solution 6: Accuracy is the extent to which a reported measurement approaches the true value of the quantity measured. A lady wants to buy a whole chicken of about 1.5 kg and red chillies of about 200 g. State which scale is suitable for each of the items and explain your answer. PAGE NO: 47 Solution 7: Light year is defined as the distance travelled by light in vacuum in one year. Solution 17: A leap year refers to a year in which February has 29 days and the total days in the year are 366 days. Secondary instruments. Solution 18: If the zero of the circular scale remains below the line of graduation then it is called positive zero error. Courses List. Introduction to physics ... Mass Measuring Instruments Stopwatch. Some of the fundamental units are metre (length), kilogram (mass), second (time), Kelvin (temperature), ampere (current), etc. Solution 20: If the zero of the circular scale lies above the line of graduation then it is called negative zero error. Solution 11: Due to constant use, there is space for the play of screw gauge but gradually this space increases with the use or wear and tear, so that when the screw is moved by rotating it in some direction, it slips in the nut and does not cover any linear distance for some rotation of the screw head. Solution 14: No, micron is not same as millimeter because micron is equal to 10-6metre while a millimeter is equal to 10-3metre. A, B, C and D show the scales of four different meters respectively. A hawker has two measuring scales, A and B.