Answer:
162 KJ
Explanation:
The electrical energy can be calculated using the formula
E = V×I×t
Where, V= voltage = 120 V
I is current in ampere = 7.5 A and t is time in seconds
1 hour = 3600 sec
Therefore, 0.05 hour = 3600×0.05 = 180 sec
Substitute the values in above equation find electrical power
E = 120×7.5×180
= 162000 J
= 162 KJ
Therefore, the electrical energy use of the microwave = 162 KJ
Frequency can be found by counting the number of troughs per second in a wave diagram.
Solution1:
0.25 min = 15 secs
a = (v - ) / t
v = 0 (stops to rest), t = 15
⇒ a = -/15
x = t + a
⇒ 10.5 = * 15 + * * 225
10.5 = * 15 -
10.5 = * 7.5
= 1.4 (m/s)
⇒ a = - (m/s^2)
Solution2:
Answer:
3117.914 m tall mountain
Explanation:
Chocolate bar gave him 2.2 Mega Joules energy
Gravitational Potential energy = mgh
now, if he store that energy entirely as gravitational potential energy then
mgh = 2.2×10^6
⇒ 72 × 9.8 × h = 2.2×10^6
⇒h = (2.2×10^6)/(72×9.8) = 3117.914 m
Answer:
E = 1580594.95 N/C
Explanation:
To find the electric field inside the the non-conducting shell for r=11.2cm you use the Gauss' law:
(1)
dS: differential of the Gaussian surface
Qin: charge inside the Gaussian surface
εo: dielectric permittivity of vacuum = 8.85 × 10-12 C2/N ∙ m2
The electric field is parallel to the dS vector. In this case you have the surface of a sphere, thus you have:
(2)
Qin is calculate by using the charge density:
(3)
Vin is the volume of the spherical shell enclosed by the surface. a is the inner radius.
The charge density is given by:
Next, you use the results of (3), (2) and (1):
Finally, you replace the values of all parameters, and for r = 11.2cm = 0.112m you obtain:
hence, the electric field is 1580594.95 N/C