Answer: 909 m/s
Explanation:
Given
Mass of the bullet, m1 = 0.05 kg
Mass of the wooden block, m2 = 5 kg
Final velocities of the block and bullet, v = 9 m/s
Initial velocity of the bullet v1 = ? m/s
From the question, we would notice that there is just an object (i.e the bullet) moving before the collision. Also, even after the collision between the bullet and wood, the bullet and the wood would move as one object. Thus, we would use the conservation of momentum to solve
m1v1 = (m1 + m2) v, on substituting, we have
0.05 * v1 = (0.05 + 5) * 9
0.05 * v1 = 5.05 * 9
0.05 * v1 = 45.45
v1 = 45.45 / 0.05
v1 = 909 m/s
Thus, the original velocity of the bullet was 909 m/s
Answer:
0.62 rad/s
Explanation:
Angular momentum is conserved.
I₁ ω₁ = I₂ ω₂
where I is moment of inertia and ω is angular velocity.
The total moment of inertia is the sum of the platform's inertia and the boy's.
(I + m r₁²) ω₁ = (I + m r₂²) ω₂
Given I = 1000 kg m², m = 50 kg, r₁ = 4.0 m, r₂ = 3.0 m, and ω₁ = 0.5 rad/s:
(1000 + 50 (4.0)²) (0.5) = (1000 + 50 (3.0)²) ω₂
900 = 1450 ω₂
ω₂ = 0.62 rad/s
Answer:
The correct answer is : a special type of experimental design where subject divides in two groups according their treatment setting.
Explanation:
A two group is a experimental design two groups are the two different groups of subjects divided by the researcher for comparing the data and result to establish relation in variables.
In normal case, one of the two groups one is a group of subjects who get treatment known as experiment or treatment group while other group is known as control group without treatment.
Thus, the correct answer is : a special type of experimental design where subject divides in two groups according their treatment setting.
Answer:
The magnitude of the induced emf is
Ф = 5.419 x 10⁻³ V
Explanation:
Given:
r = 23.0 cm = 0.23 m
β₁ = 0.50 T
β₂ = 2.50 * 0.50 T = 1.25 T
Calculate the magnitude of the induced emf the magnetic field is increasing
Ф = A * Δβ / Δt
A = π * r² = π * 0.23² m = 0.166 m²
Ф = 0.166m² * (1.25 - 0.5) T / 23 s
Ф = 5.419 x 10⁻³ V
Answer:
a)Change in the speed = 1.41 m/s
b)The final speed will be 3.11 m/s
Explanation:
Given that
Acceleration ,a= 4.7 x 10⁻³ m/s²
a)
We know that
v= u + a t
v=final speed ,u=initial speed
t= time ,a= acceleration
Change in the speed
v- u = a t
t= 5 min = 5 x 60 s = 300 s
v- u = 4.7 x 10⁻³ x 5 x 60 m/s
v-u = 1.41 m/s
Change in the speed = 1.41 m/s
b)
Given that
u= 1.7 m/s
v-u = 1.41 m/s
v= 1.7 + 1.41 m/s
v=3.11 m/s
The final speed will be 3.11 m/s
