Answer:
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%.
Answer:
b) in a direction that makes its potential energy decrease.
Explanation:
- As the electric field has the direction that would take a positive test charge under its sole influence, the positive test charge, will have an increase in its kinetic energy.
- Due to the conservation of energy, in absence of non-conservative forces, this increment must be equal and opposite to the change in electric potential energy, which will be always negative, independent of the sign of the charge.
Answer:
C. precipitation
Explanation:
if clouds store too much water from evaporation, it will rain which is precipitation
Answer:
400ft. 32ft/s -32ft/s
Explanation:
In reality the gravitational acceleration is 9.81 so the quadratic coefficient of the function should be 9.81/2
Anyway for the sake of assumtion let us takes=160t-16t^2
ds/dt=160-32t=0
t=160/32= 5 seconds.
s=160*160/32-16*(160/32)^2= 400 mts
s=384 mts
160t-16t^2=384
i.e
16t^2-160t+384=0
t^2-10t+24=0
(t-6)(t-4)=0
t=[4,6]
we have to take t=4 because it is all the up i.e <5
velocity =v=ds/dt=160-32t
v=160-32*4=32 ft/sec still going up
for all the way down take t=6 whuch is >5
v=160-6*32=-32 ft/sec (falling down!!!)