Answer:
Explanation:
Ruler. A steel ruler aids the measurement and layout of straight lines. The ruler, also called "straightedge" or "straight-edged ruler," is a long, thin strip of wood, metal or plastic marked with increments of measurement.
Measuring Tape. The modern measuring tape's roughly palm-sized casing contains a coiled strip of metal marked with increments of measurement. The metal strip, called "tape," attaches to a spring which automatically retracts the tape into the casing following use.
Walking Tape Measure. The walking tape measure, also called "surveyor's measure," records the distance traveled by a wheel. An operator pushes the measure's wheel, similar to a bicycle wheel, by a handle as an attached ticker box displays feet or meters in the same format as a car's odometer.
Laser Measure. The laser measure offers point and shoot distance measurement. In its most basic form, a laser measure is a hand-held electronic device with a digital display.
Answer: A, C and D
Explanation:
Interference occurs when two waves superimpose to form a wave having a smaller or larger amplitude.
Constructive interference is said to occur when two waves superimpose to produce a wave having larger amplitude. It occurs for the waves having phase difference of multiple of 2π. On the other hand, destructive interference occurs for the waves having phase difference π, 3π, ..and so on.
In the given picture, the bright regions represent constructive interference where as the dark ones between them represent destructive interference. Thus, the correct letters representing constructive interference are: A, C and D.
You can observe this law in practice if <span>a ray of light reflects off of a flat mirror.
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Law of reflection states that both direction of both incoming and outgoing rays of light make the same angle with respect to surface normal.
Answer:
JC⁻¹
Explanation:
= mass of water added to calorimeter = 94.8 g
= initial temperature of the water added = 60.4 C
= specific heat of water = 4.184 Jg⁻¹C⁻¹
= mass of water available to calorimeter = 94.8 g
= initial temperature of the water in calorimeter = 22.3 C
= final equilibrium temperature = 35 C
= Heat gained by calorimeter
Using conservation of heat
Heat gained by calorimeter = Heat lost by water added - heat gained by water in calorimeter
J
= Change in temperature of calorimeter
Change in temperature of calorimeter is given as
C
Heat capacity of calorimeter is given as
JC⁻¹
Question 1's answer is, if we change the length of the string allowed to vibrate, then the frequency (and pitch) of the string vibration will change. This is because the tension of the string determines the pitch.
Question 2's answer is 2. This can be solved by doing simple division. 30/15 = 2.
Question 3's answer is short bars. Each bar on a xylophone produces a different pitch; the shorter the bar, the higher the pitch.
Hope this helps.
