Answer:
The temperature of silver at this given resistivity is 2971.1 ⁰C
Explanation:
The resistivity of silver is calculated as follows;
where;
Rt is the resistivity of silver at the given temperature
Ro is the resistivity of silver at room temperature
α is the temperature coefficient of resistance
To is the room temperature
T is the temperature at which the resistivity of silver will be two times the resistivity of iron at room temperature
Resistivity of iron at room temperature = 9.71 x 10⁻⁸ ohm.m
When silver's resistivity becomes 2 times the resistivity of iron, we will have the following equations;
Therefore, the temperature of silver at this given resistivity is 2971.1 ⁰C
Answer:
4.3 m/s
Explanation:
a = rate at which the automobile loses speed = - 7.2 m/s²
v₀ = initial maximum speed of automobile
t' = reaction time for applying the brakes = 0.55 s
d = distance available for stopping the vehicle = 3.6 m
d' = distance traveled while applying the brakes = v₀ t' = (0.55) v₀
v = final speed after the vehicle comes to stop = 0 m/s
Using the equation
v² = v₀² + 2 a (d - d' )
0² = v₀² + 2 (- 7.2) (3.6 - (0.55) v₀)
v₀ = 4.3 m/s
Answer:
Explanation:
The uncertainty in energy is given by
here h is plank's constant which value is and
is the time interval which is given as
So using all the parameters the smallest possible uncertainty in electrons energy is
Answer:
kilogram
Explanation:
Answer:
SI base units of mass=KG
Answer: the answer i for c is yes 0& 10
Explanation:
Answer:
-847.2J
Explanation:
First find the acceleration from v^2= u^2 + 2as
v= 2.5 m/s
u= 1.3 m/s
a???
s=6.00
a= v^2-u^2/2s
a= (2.5)^2-(1.3)^2/2× 6
a= 0.38ms^-2
From Newtons second law:
(Force applied cos Θ) - (Frictional force) = ma
Frictional force = ma- (Force applied cos Θ)
Frictional force= (18.8×0.38) - (165 cos 26°)
Frictional force= 7.144- 148.3= -141.2N
Therefore,
Work done by friction = Frictional force × distance covered
= -141.2N × 6= -847.2J
Answer:
W = –847J
Explanation:
Given m = 18.8kg, F = 165N, θ = -26° (below the horizontal, s = 6.0m, u = 1.30m/s and v = 2.50m/s
In this problem, two forces act on the chair; the forward force F and the frictional force f. We would apply newton's second law to find the frictional force f after which we can calculate the workdone by the frictional force f×s.
But for us to apply newton's second law, we need to know the acceleration of the chair cause by the net force.
From constant acceleration motion equations
v² = u² + 2as
2.5² = 1.30² + 2a×6
6.25 = 1.69 +12a
12a = 6.25 – 1.69
12a = 4.56a
a = 4.56/12
a = 0.38m/s
By newton's second law the net sum of forces equals m×a
The force F has horizontal and vertical and components. It is the horizontal component of this force that pushes the chair against friction.
Fx and f are oppositely directed.
So
Fx – f =ma
165cos(-26) – f = 18.8×0.38
148.3 – f = 7.14
f = 148.3 – 7.14
f = 141.2N
Workdone = -fs = –141.2×6.00 = –847J
W = –847J
Work is negative because it is done by a force acting on the chair in a direction opposite (antiparallel) to that of the intended motion.
b. Find the wavelength of the final note.
c. Assume the choir sings the melody with a uniform sound level of 70.0 dB. Find the pressure amplitude of the initial note.
d. Find the pressure amplitude of the final note.
e. Find the displacement amplitude of the initial note.
f. Find the displacement amplitude of the final note.
Answer:
Detailed step wise solution is attached below
Explanation:
(a) wavelength of the initial note 2.34 meters
(b) wavelength of the final note 0.389 meters
(d) pressure amplitude of the final note 0.09 Pa
(e) displacement amplitude of the initial note 4.78*10^(-7) meters
(f) displacement amplitude of the final note 3.95*10^(-8) meters