Assume the wooden piece prevents the balloon from rising, is not so heavy as to cause the balloon to descend. and the 15 m/s is horizontal velocity “riding the wind,” That horizontal velocity does not affect the time the wood will take to reach the ground after release. Initial vertical velocity is zero.
s = u t + 1/2 g t^2
s is the height above ground, 300 m.
u is initial vertical velocity, zero.
t is time to reach the ground.
g is acceleration of gravity near Earth, 9.8 m/s^2.
300 m = 0 t + 1/2 (9.8 m/s^2) t^2
300 m = (4.9 m/s^2) t^2
61.22 s^2 = t^2
7.82 seconds = t
In a parallel circuit, the equivalent resistance is the reciprocal of (the sum of the individual reciprocals).
1/R = 1/10 + 1/21 + 1/13
1/R = 0.225 mhos
R = 4.45 ohms
I = V / R
The total current out of the battery is
I = (9v)/(4.45ohms)
I = 2.02 Amperes
As the total current leaves the battery, it splits into 3 paths, and each resistor gets part of it. The 10ohm resistor gets the most current; the 21ohm resistor gets the least current. After flowing through the resistors, the 3 currents join and add up to 2.02 Amperes again, and the same current returns to the battery.
Each resistor has the same 9v of EMF across it.
Answer:
a. v₁ = 16.2 m/s
b. μ = 0.251
Explanation:
Given:
θ = 15 ° , r = 100 m , v₂ = 15.0 km / h
a.
To determine v₁ to take a 100 m radius curve banked at 15 °
tan θ = v₁² / r * g
v₁ = √ r * g * tan θ
v₁ = √ 100 m * 9.8 m/s² * tan 15° = 16.2 m/s
b.
To determine μ friction needed for a frightened
v₂ = 15.0 km / h * 1000 m / 1 km * 1h / 60 minute * 1 minute / 60 seg
v₂ = 4.2 m/s
fk = μ * m * g
a₁ = v₁² / r = 16.2 ² / 100 m = 2.63 m/s²
a₂ = v₂² / r = 4.2 ² / 100 m = 0.18 m/s²
F₁ = m * a₁ , F₂ = m * a₂
fk = F₁ - F₂ ⇒ μ * m * g = m * ( a₁ - a₂)
μ * g = a₁ - a₂ ⇒ μ = a₁ - a₂ / g
μ = [ 2.63 m/s² - 0.18 m/s² ] / (9.8 m/s²)
μ = 0.251
The correct option is (A) 2.5 m/s
Explanation:
Since,
v = fλ ---- (1)
where v = speed of the wave
f = frequency of the wave = 5 Hz
λ = wavelength of the wave = 0.5
Plug in the value in (1):
(1) => v = 5 * 0.5
v = 2.5 m/s
