Answer:
V = 4.826m/s, 716N
Explanation:
At the lowest swinging point, the net force acting on the child is equal to the centripetal force and it could be represented as
F = mv^2/r
2T-mg =mv^2/r
r(2T-mg) = mv^2
Divide both sides by m
r(2T-mg)/m = mv^2/m
r(2T/m-g) = v^2
V= √ r(2T/m-g)
Where v is the velocity
r is the length of the chain
m is the mass of the child in kg
T is the tension in Newton
g is the acceleration due to gravity
Given that g = 9.8m/s^2
T = 358N
m = 41.0kg
r = 3.04m
Substituting the values into the formula
V = √ 3.04( 2*358/41 -9.89
V = √ 3.04 ( 716/41 - 9.8 )
V = √3.04 ( 17.463-9.8 )
V = √3.04( 7.6634)
V = √23.2967
V = 4.826m/s
For the second part which is the tension in the two chains
N - m*g = m*(v^2 / r)
N - (41)*(9.81) = (41)*(4.826^2 / 3.04)
N - 402.21 = 41×7.66
N - 402.21 = 314.112
N = 402.21 + 314.112
N = 716.332 newton
Approximately = 716N
Or alternatively, since there are two chains holding the swing, of which each chain is acted upon by a 358N tension. Hence = 2T
2*358 = 716N
The difference in the speeds of the two types of waves
is (8.9 - 5.1) = 3.8 km/sec.
In 73 sec, the faster one pulls ahead of the slower one
by (73 x 3.8) = <em>277.4 km</em>.
3. An object will float if its density is less than the matter it is submerged in.
If it sinks in water, its density is more than 1. If it floats in glycerin, its density is less than 1.26.
Answer:
Explanation:
mass of string = .0125 / 9.8
= 1.275 x 10⁻³ kg
Length of string l = 1.5 m .
m = mass per unit length
= ( .1.275 / 1.5) x 10⁻³ kg/m
m = .85 x 10⁻³ kg/m
wave equation: y(x,t) = (8.50 mm)cos(172 rad/m x − 4830 rad/s t)
compare with equation of wave
y(x,t) = Acos(K x − ω t)
ω ( angular velocity ) = 4830 rad/s
k = 172 rad/m
Velocity = ω / k
= 4830/172 m /s
= 28.08 m /s
velocity of wave =
28.08 =
788.48 = W / .85 X 10⁻³
W = 670 x 10⁻³ N .
c ) wave length
wave length =2π / k
= 2 x 3.14 / 172
= .0365 m
no of wave lengths over whole length of string
= 1.5 / .0365
= 41
d )
equation for waves traveling down the string
= (8.50 mm)cos(172 rad/m x + 4830 rad/s t)
Answer:
<h3>therefore , option (b) is correct!!</h3>
hope helpful~