Answer:
1.) Micrometres screw gauge
2.) Tape rule.
Explanation:
Given that the diameter and the length of a thin wire, approximately 1m in length, are measured as accurately as possible.
what are the best instruments to use ?
To measure the diameter of a thin wire, the best instrument to use is known as micrometres screw gauge.
And to measure the length of a thin wire up to 1 m, the measuring device can be tape rule or long metre rule.
Answer:
Explanation:
The power of each of the speakers is 0.535 W. At a distance d intensity of sound can be found by the following formula
Intensity of sound = Power / 4π d²
= .535 / 4 x 3.14 x (27.3/2)²
= 2.286 x 10⁻⁴ J m⁻² s⁻¹
Intensity of sound due to other source = 5.715 x 10⁻⁵J m⁻² s⁻¹
Total intensity = 2 x 2.286 x 10⁻⁴J m⁻² s⁻¹
= 4.57 x 10⁻⁴J m⁻² s⁻¹
b ) In this case, man is standing at distances 18.15 m and 9.15 m from the sources .
The total intensity of sound reaching him is as follows
0.535 / (4 π x18.15² ) + 0.535 / (4 π x9.15² )
= 1.293 x 10⁻⁴ + 5.087 x 10⁻⁴
= 6.38 x 10⁻⁴J m⁻² s⁻¹
Answer:
The velocity is 40 ft/sec.
Explanation:
Given that,
Force = 3200 lb
Angle = 30°
Speed = 64 ft/s
The resistive force with magnitude proportional to the square of the speed,
Where, k = 1 lb s²/ft²
We need to calculate the velocity
Using balance equation
Put the value into the formula
Put the value of k
At terminal velocity 
So, 
Hence, The velocity is 40 ft/sec.
Polarizing filters: used to show light has some properties of a wave in that way of property is that light can be thought of as traveling forward in waves, with the <span>wave. sorry if this is too late but google is good</span>
