99 asap
which of the following would be used in luminosity calculations?
candela
joule
kilogram
ampere
2. work, measured in joules, is force × distance.
if the unit of force is kg⋅m/s2 , then which of the following is the correct description of joule in terms of si base units?
kg⋅m/s3
kg⋅m/s2
kg⋅m/s
kg⋅m2/s2
3.in an experiment, you calculate newton's universal gravitational constant to be 7.34×10−11 n⋅m2/kg2 . the accepted value is 6.67×10−11 n⋅m2/kg2 .
what is your percent error?
0.01%
0.1%
5%
10%

1) Joule

2) kgm²/s²

3) 10%

Explanation:

Question 1)

Luminosity is defined as the total amount of energy released from an object in a unit amount of time.

This means Luminosity is the ratio of energy and time.

Unit of Energy is Joules and Unit of Time is seconds, so unit of Luminosity would be Joule per second or Watts.

So, from the given options, the unit which would be used in Luminosity calculations is Joule.

Question 2)

Work = Force x Distance

SI unit of Work is Joule

SI unit of Force is Newton or kgm/s²

SI unit of Distance is meter(m)

Unit of Work = Unit of Force x Unit of Distance

Joule = kgm/s² x m

Joule = kgm²/s²

This means, the correct description of joule in terms of SI base units is kgm²/s²

Question 3)

Value of gravitational constant from the experiment = Nm²/kg²

The accepted or actual value of the gravitational constant =   Nm²/kg²

We need to calculate the percentage error. Percentage error is defined as:

Here, original value is the accepted value. Using the values in this formula, we get:

Thus, this means the percentage error in the calculation of gravitational constant was 10%.

  distance on the y-axis and time on the x-axis.

explanation:

the instantaneous velocity = change in position/time taken

the slope of the graph should give instantaneous velocity.

  slope of a graph = change in value of y -axis / change in values of x -axis

  comparing both the equations

    change in value of y -axis = change in position

  change in values of x -axis = time taken

so position values should be on the y axis and time values should be on the x axis.

distance on the y-axis and time on the x-axis.

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia