Answer:12.8°c
Explanation:
specific heat capacity of copper(c)=0.39J*g°c
Mass(m)=20grams
Quantity of heat(Q)=100joules
Temperature rise(@)=?
@=Q/(mxc)
@=100/(20x0.39)
@=100/7.8
@=12.8°c
Answer
given,
x = (3.9 cm)sin[(9.3 rad/s)πt]
general equation of displacement
x = A sin ω t
A is amplitude
now on comparing
c) Amplitude =3.9 cm
a) frequency =


f = 4.65 Hz
b) period of motion


T = 0.215 s
d) time when displacement is equal to x= 2.6 cm
x = (3.9 cm)sin[(9.3 rad/s)πt]
2.6 = (3.9 cm)sin[(9.3 rad/s)πt]
sin[(9.3 rad/s)πt] = 0.667
9.3 π t = 0.73
t = 0.025 s
Answer:
292.3254055 W/m²
469.26267 V/m

Explanation:
P = Power of bulb = 90 W
d = Diameter of bulb = 7 cm
r = Radius = 
= Permittivity of free space = 
c = Speed of light = 
The intensity is given by

5% of this energy goes to the visible light so the intensity is

The visible light intensity at the surface of the bulb is 292.3254055 W/m²
Energy density of the wave is

Energy density is also given by

The amplitude of the electric field at this surface is 469.26267 V/m
Amplitude of a magnetic field is given by

The amplitude of the magnetic field at this surface is 
Brown dwarf is the first box
White dwarf is the second box
Black dwarf is the third box
Red giant is the fourth box
And
Black hole is the last box
Answer:
angular speed of both the children will be same
Explanation:
Rate of revolution of the merry go round is given as
f = 4.04 rev/min
so here we have

here we know that angular frequency is given as



now this is the angular speed of the disc and this speed will remain same for all points lying on the disc
Angular speed do not depends on the distance from the center but it will be same for all positions of the disc