CHAPTER#01
SHORT RESPONSE QUESTIONS
Q:1 How physics plays an important role in our life
Ans: Physics extends to your daily life to describe the motion, forces, and energy of the ordinary
experience. Physics is at work in tasks such as walking, driving a car or using a phone. Knowledge of
physics is helpful in everyday situations as well as in non-scientific tasks. For example, physics helps you
understand:
How food is cooked in a microwave oven,
Why a radiator helps to dissipate the heat of a car engine, and
Why a white ceiling helps to keep the inside of a house cool.
Q:2 Estimate your age in minutes and seconds ?
Ans: Type in your age in years - multiply by 365 to get it in days, multiply that by 24 to get it in
hours, then by 60 to get minutes - and finally, multiply by 60 again to get it in seconds.
Q:3 What base quantities are involved in these derived physical quantities; force, pressure,
power and charge.
Ans: Force: Mass, Length, and Time
* Force is derived from the base quantities of mass, length, and time, according to the equation
F = ma, where F is force, m is mass, and a is acceleration.
Pressure: Mass, Length, and Time
* Pressure is derived from the base quantities of mass, length, and time, and is defined as force per unit
area, or P = F/A, where P is pressure, F is force, and A is area.
Power: Mass, Length, and Time
* Power is derived from the base quantities of mass, length, and time, and is the rate of doing work or the
rate of energy transfer, defined as P = W/t, where P is power, W is work, and t is time.
Charge: Electric Current and Time
* Electric charge is a fundamental physical quantity that is not derived from other base quantities.
However, the derived quantity of electric current, which is the rate of flow of electric charge, is defined in
terms of the base quantities of electric current (ampere) and time.
Q:4 Show that prefix micro is thousand time smaller than prefix milli.
Ans: This is because 10^-6 (micro) is 1000 times smaller than 10^-3 (milli). To put it in
perspective, if you have a millimeter, there are 1000 micrometers in it. Hence, the prefix micro is
a thousand times smaller than the prefix milli.
Q:5 Justify that displacement is a vector quantity while energy is a scalar quantity.
, Ans: The displacement is a vector (straight line in a certain direction). The energy you used to
walk there (calories burned) is a scalar value (amount of energy), not a vector (no direction
involved)
Q:6 Screw gauge can give more precise length has Vernier calipers. Briefly explain why?
Ans: As compare to Vernier calipers, screw gauge is more precise because the least count of
Vernier calipers is 0.1 mm and for screw gauge it is 0.01 mm. So, a screw gauge can measure
more precisely than a Vernier caliper.
Q:7 Differentiate between mechanical stop watch and digital stop watch.
Ans: Mechanical stopwatches are powered by a mainspring, which must be wound up by
turning the knurled knob at the top of the stopwatch.
Digital electronic stopwatches are available which, due to their crystal oscillator timing
element, are much more accurate than mechanical timepieces.
Q:8 How measuring cylinder is used to measure volume of an irregular shaped stone?
Ans: Because many objects are not regularly shaped their volume cannot be determined using a volume
formula. The volume of these objects can be found by water displacement. A volume of water sufficient
to cover the object is placed in a graduated cylinder and the volume read. The object is added to the
cylinder and the volume read again. The difference between the two volumes is the volume of the
object. This method is demonstrated using the same battery used above.
Q: 9 What precautions should be kept in mind while taking measurement using measuring cylinder?
Ans: Precautions to be taken while measuring the volume of the liquid with a measuring
cylinder:
Make sure the measuring cylinder is placed on a flat surface.
Take care of the meniscus and take the reading accurately.
Avoid parallax error while taking the measurement.
SHORT RESPONSE QUESTIONS
Q:1 How physics plays an important role in our life
Ans: Physics extends to your daily life to describe the motion, forces, and energy of the ordinary
experience. Physics is at work in tasks such as walking, driving a car or using a phone. Knowledge of
physics is helpful in everyday situations as well as in non-scientific tasks. For example, physics helps you
understand:
How food is cooked in a microwave oven,
Why a radiator helps to dissipate the heat of a car engine, and
Why a white ceiling helps to keep the inside of a house cool.
Q:2 Estimate your age in minutes and seconds ?
Ans: Type in your age in years - multiply by 365 to get it in days, multiply that by 24 to get it in
hours, then by 60 to get minutes - and finally, multiply by 60 again to get it in seconds.
Q:3 What base quantities are involved in these derived physical quantities; force, pressure,
power and charge.
Ans: Force: Mass, Length, and Time
* Force is derived from the base quantities of mass, length, and time, according to the equation
F = ma, where F is force, m is mass, and a is acceleration.
Pressure: Mass, Length, and Time
* Pressure is derived from the base quantities of mass, length, and time, and is defined as force per unit
area, or P = F/A, where P is pressure, F is force, and A is area.
Power: Mass, Length, and Time
* Power is derived from the base quantities of mass, length, and time, and is the rate of doing work or the
rate of energy transfer, defined as P = W/t, where P is power, W is work, and t is time.
Charge: Electric Current and Time
* Electric charge is a fundamental physical quantity that is not derived from other base quantities.
However, the derived quantity of electric current, which is the rate of flow of electric charge, is defined in
terms of the base quantities of electric current (ampere) and time.
Q:4 Show that prefix micro is thousand time smaller than prefix milli.
Ans: This is because 10^-6 (micro) is 1000 times smaller than 10^-3 (milli). To put it in
perspective, if you have a millimeter, there are 1000 micrometers in it. Hence, the prefix micro is
a thousand times smaller than the prefix milli.
Q:5 Justify that displacement is a vector quantity while energy is a scalar quantity.
, Ans: The displacement is a vector (straight line in a certain direction). The energy you used to
walk there (calories burned) is a scalar value (amount of energy), not a vector (no direction
involved)
Q:6 Screw gauge can give more precise length has Vernier calipers. Briefly explain why?
Ans: As compare to Vernier calipers, screw gauge is more precise because the least count of
Vernier calipers is 0.1 mm and for screw gauge it is 0.01 mm. So, a screw gauge can measure
more precisely than a Vernier caliper.
Q:7 Differentiate between mechanical stop watch and digital stop watch.
Ans: Mechanical stopwatches are powered by a mainspring, which must be wound up by
turning the knurled knob at the top of the stopwatch.
Digital electronic stopwatches are available which, due to their crystal oscillator timing
element, are much more accurate than mechanical timepieces.
Q:8 How measuring cylinder is used to measure volume of an irregular shaped stone?
Ans: Because many objects are not regularly shaped their volume cannot be determined using a volume
formula. The volume of these objects can be found by water displacement. A volume of water sufficient
to cover the object is placed in a graduated cylinder and the volume read. The object is added to the
cylinder and the volume read again. The difference between the two volumes is the volume of the
object. This method is demonstrated using the same battery used above.
Q: 9 What precautions should be kept in mind while taking measurement using measuring cylinder?
Ans: Precautions to be taken while measuring the volume of the liquid with a measuring
cylinder:
Make sure the measuring cylinder is placed on a flat surface.
Take care of the meniscus and take the reading accurately.
Avoid parallax error while taking the measurement.
