Answer:
1. 20.54m/s
2. 1.52s
Explanation:
QUESTION 1:
The speed the stone impact the ground is the final speed/velocity, which can be calculated using the formula:
v² = u² + 2as
Where;
v = final velocity (m/s)
u = initial velocity (m/s)
a = acceleration due to gravity (m/s²)
s = distance (m)
From the provided information, u = 5.65m/s, v = ?, s = 19.9m, a = 9.8m/s²
v² = 5.65² + 2 (9.8 × 19.9)
v² = 31.9225 + 2 (195.02)
v² = 31.9225 + 390.04
v² = 421.9625
v = √421.9625
v = 20.5417
v = 20.54m/s
QUESTION 2:
Using v = u + at
Where v = final velocity (m/s) = 20.54m/s
t = time (s)
u = initial velocity (m/s) = 5.65m/s
a = acceleration due to gravity (m/s²)
v = u + at
20.54 = 5.65 + 9.8t
20.54 - 5.65 = 9.8t
14.89 = 9.8t
t = 14.89/9.8
t = 1.519
t = 1.52s
By definition, the potential energy is:
U = qV
Where,
q: load
V: voltage.
Then, the kinetic energy is:
K = mv ^ 2/2
Where,
m: mass
v: speed.
As the power energy is converted into kinetic energy, we have then:
U = K
Equating equations:
qV = mv ^ 2/2
From here, we clear the speed:
v = root (2qV / m)
Substituting values we have:
v = root ((2 * (1.60218 × 10 ^ -19) * 3600) /9.10939×10^-31))
v = 3.56 × 10 ^ 7 m / s
Then, the centripetal force is:
Fc = Fm
mv ^ 2 / r = qvB
By clearing the magnetic field we have:
B = mv / qr
Substituting values:
B = (9.10939 × 10 ^ -31) * (3.56 × 10 ^ 7) / (1.60218 × 10 ^ -19) * 0.059
B = 3.43 × 10 ^ -3 T
Answer:
A magnetic field that must be experienced by the electron is:
B = 3.43 × 10 ^ -3 T
Answer:
5) 13 revolutions (approximately)
Explanation:
We apply the equations of circular motion uniformly accelerated :
ωf²= ω₀² + 2α*θ Formula (1)
Where:
θ : angle that the body has rotated in a given time interval (rad)
α : angular acceleration (rad/s²)
ω₀ : initial angular speed ( rad/s)
ωf : final angular speed ( rad/s)
Data:
ω₀ = 18 rad/s
ωf = 0
α = -2 rad/s² ; (-) indicates that the wheel is slowing
Revolutions calculation that turns the wheel until it stops
We apply the formula (1)
ωf²= ω₀² + 2α*θ
0 = (18)² + 2( -2)*θ
4*θ = (18)²
θ = (18)²/4 = 81 rad
1 revolution = 2π rad
θ = 81 rad * 1 revolution / 2πrad
θ = 13 revolutions approximately
Answer:
D = 18000 kg/m3
V = 2.5*10{-7}m3
Explanation:
From the Archimedes principle,
Weight of fluid displaced = W_{air} - W_{water}
W_{air} = 4.5 gm
W_{water} = 4.25 gm
![W = [4.5 - 4.25]*9.81*10^{-3}](https://tex.z-dn.net/?f=W%20%3D%20%5B4.5%20-%204.25%5D%2A9.81%2A10%5E%7B-3%7D)
W = 2.4525*10{-3} N
D = 18000 kg/m3
b) object Volume can be obtained as ,
V = 2.5*10{-7}m3
