Answer:
a) m₁ = 1.41 kg
, b) m₂ = 2.65 kg
Explanation:
For this exercise we will use Newton's second law
Block 1
T - W₁ = m₁ a
Block 2
W₂ - T = m₂ a
We have selected the positive block 1 rising and block two lowering, as the pulley has no friction does not affect the movement
Let's use kinematics to look for acceleration
y = v₀ t + ½ a t²
As part of the rest the initial speed is zero
a = 2 y / t²
a = 2 6.00 / 2²
a = 3 m / s²
Let's replace in the equation of block 1
a) T = m₁ g + m₁ a
m₁ = T / (g + a)
m₁ = 18.0 / (9.8 + 3)
m₁ = 1.41 kg
b) we substitute in the equation of block 2
W₂ - T = m₂ a
m₂ g - m₂ a = T
m₂ = T / (g-a)
m₂ = 18.0 / (9.8 -3)
m₂ = 2.65 kg
Answer:
Absolute zero is where the particles/molecules are not moving at all, meaning that there is no heat.
This means that the answer is:
1. All particles are moving and this movement allows us to measure the thermal energy of an object or substance. If the particles were able to completely stop moving this would be called reaching absolute zero.
Answer:
The mass is inversely proportional to the acceleration so the acceleration a1 is twice that acceleration a2
Explanation:
The force of friction and the kinetic force make the law of mass in moving so
The forces are the same however at the moment to determinate the acceleration
are constant because they make the same motion however the difference of mass make the acceleration difference
Answer:
7.875 ft/s
Explanation:
L = 15 ft
dx/dt = 3 ft/s
x = 9 ft
Let the top of ladder is coming down with the rate of dy/dt.
use Pythagorean theorem
L^2 = x^2 + y^2 .... (1)
Differentiate both sides with respect to t
0 = 2 x dx/dt + 2y dy/dt
x dx/dt = - y dy/dt
When, x = 9 ft then y = ? . Put this in equation (1)
15^2 = 9^2 + y^2
225 - 81 = y^2
y = 12 ft
So
dy/dt = - x (dx/dt) / y = - 9 (3) / 12 = - 9/4 ft/s
Let A be the area of the triangle
A = 1/2 (base)(height)
A = 1/2 (x y)
Differentiate both sides with respect to t
dA/dt = 0.5 (y dx/dt + x dy/dt)
dA/dt = 0.5 [ 12 (3) - 9 (9/4)]
dA/dt = 0.5(36 - 81 /4) = 31.5 / 4 = 7.875 ft/s
Explanation:
Kinetic Energy Formula = ½mv²
- ½×800kg×(23m/s)²
- 400kg×529m²/s²
- 211600 kg•m²/s²
- 211700 joule Answer