We are given with the specific heat capacity of ethanol, the mass of the sample and the temperature change to determine the total amount of heat to raise the temperature. The formula to be followed is H = mCpΔT. Upon subsituting, H = 79 g * 2.42 J/gC *(385-298)C = 16.63 kJ
Answer:
The awnser is d
Explanation:
i know cause i took the test
Answer: q = -52.5 μC
Explanation:
The complete question is given thus;
A point charge Q moves on the x-axis in the positive direction with a speed of 280 m/s. A point P is on the y-axis at y=+70mm. The magnetic field produced at the point P, as the charge moves through the origin, is equal to -0.30uTk. What is the charge Q? (uo=4pi x 10^-7 T m/A).
SOLVING:
from the given parameters we can solve this problem.
Given that the
Speed = 280 m/s
y = 70mm
B = -30 * 10⁻⁶T
Using the equation for magnetic field we have;
Β = μqv*r / 4πr²
making q (charge) the subject of formula we have that;
q = B * 4 *πr² / μqv*r
substituting the values gives us
q = (-0.3*10⁻⁶Tk * 4π * 0.07²) / (4π*10⁻⁷ * 280 ) = - [14.7 * 10⁻¹⁰k / 2.8 * 10⁻⁵ k ]
q = -52.5 μC
cheers i hope this helped !!!
Give that,
The frequency range the dog can hear is 15Hz to 50,000Hz
The wavelength of sound in air at 20°C =?
Speed of sound is 344
The frequency corresponding to the lower cut-off point is the lowest frequency which his 15Hz
F=15Hz
The relationship between the wavelength, speed and frequency is given as
v=fλ
Then,
λ=v/f
λ=v/f
λ=344/15
λ=22.93m
KE=1/2 mv^2
=1/2(150kg)(15m/s)^2
=16875 kgms^-2