Answer:
a) 6.4 x 10^-12 cm^3
b) 17 x 10^-6 mm^2
Explanation
a). The shape is assumed to be spherical The volume = volume of a sphere = \frac{4}{3} \pi r^3
3
4
πr
3
V = \frac{4}{3}*3.142* 1.15^3
3
4
∗3.142∗1.15
3
= 6.3715 μm^3
1 μm^3 = 10^-12 cm^3
6.3715 μm^3 = 6.3715 x 10^-12 cm^3
==> 6.4 x 10^-12 cm^3
Answer:
6 cm long
Explanation:
F = 4110N
Vo(speed of sound) = 344m/s
Mass = 7.25g = 0.00725kg
L = 62.0cm = 0.62m
Speed of a wave in string is
V = √(F / μ)
V = speed of the wave
F = force of tension acting on the string
μ = mass per unit density
F(n) = n (v / 2L)
L = string length
μ = mass / length
μ = 0.00725 / 0.62
μ = 0.0116 ≅ 0.0117kg/m
V = √(F / μ)
V = √(4110 / 0.0117)
v = 592.69m/s
Second overtone n = 3 since it's the third harmonic
F(n) = n * (v / 2L)
F₃ = 3 * [592.69 / (2 * 0.62)
F₃ = 1778.07 / 1.24 = 1433.927Hz
The frequency for standing wave in a stopped pipe
f = n (v / 4L)
Since it's the first fundamental, n = 1
1433.93 = 344 / 4L
4L = 344 / 1433.93
4L = 0.2399
L = 0.0599
L = 0.06cm
L = 6cm
The pipe should be 6 cm long
Answer:
the initial velocity of the car is 12.04 m/s
Explanation:
Given;
force applied by the break, f = 1,398 N
distance moved by the car before stopping, d = 25 m
weight of the car, W = 4,729 N
The mass of the car is calculated as;
W = mg
m = W/g
m = (4,729) / (9.81)
m = 482.06 kg
The deceleration of the car when the force was applied;
-F = ma
a = -F/m
a = -1,398 / 482.06
a = -2.9 m/s²
The initial velocity of the car is calculated as;
v² = u² + 2ad
where;
v is the final velocity of the car at the point it stops = 0
u is the initial velocity of the car before the break was applied
0 = u² + 2(-a)d
0 = u² - 2ad
u² = 2ad
u = √2ad
u = √(2 x 2.9 x 25)
u =√(145)
u = 12.04 m/s
Therefore, the initial velocity of the car is 12.04 m/s
