Multiplying the power of any signal by 5 can be described as
an increase of 6.99 dB .
If the whistle blew at 70 dB initially, and its sound power became
multiplied by 5, and the whistle and the listener both stayed in
the same places, then the listener would tell you that the whistle
was now blowing at 76.99 dB .
(More likely, he would report "77 dB" as he held his ears and winced.)
Answer:
1.1 m/s²
Explanation:
From the question,
F -mgμ = ma.................... Equation 1
Where F = applied force, m = mass of the apple cart, g = acceleration due to gravity, μ = coefficient of friction., a = acceleration of the apple cart.
Given: F = 115 N, m = 25 kg, μ = 0.35
Constant: g = 10 m/s²
Substitute these values into equation 2
115-(25×10×0.35) = 25×a
115-87.5 = 25a
25a = 27.5
a = 27.5/25
a = 1.1 m/s²
Answer:
Fc=5253
N
Explanation:
Answer:
Fc=5253
N
Explanation:
sequel to the question given, this question would have taken precedence:
"The 86.0 kg pilot does not want the centripetal acceleration to exceed 6.23 times free-fall acceleration. a) Find the minimum radius of the plane’s path. Answer in units of m."
so we derive centripetal acceleration first
ac (centripetal acceleration) = v^2/r
make r the subject of the equation
r= v^2/ac
ac is 6.23*g which is 9.81
v is 101m/s
substituing the parameters into the equation, to get the radius
(101^2)/(6.23*9.81) = 167m
Now for part
( b) there are two forces namely, the centripetal and the weight of the pilot, but the seat is exerting the same force back due to newtons third law.
he net force that maintains circular motion exerted on the pilot by the seat belts, the friction against the seat, and so forth is the centripetal force.
Fc (Centripetal Force) = m*v^2/r
So (86kg* 101^2)/(167) =
Fc=5253
N
Answer: -33.3 * 10^9 C/m^2( nC/m^2)
Explanation: In order to solve this problem we have to use the gaussian law, the we have:
Eoutside =0 so teh Q inside==
the Q inside= 4.6 nC/m*L + σ *2*π*b*L where L is the large of the Gaussian surface and b the radius of the shell.
Then we simplify and get
σ= -4.6/(2*π*b)= -33.3 nC/m^2
