Answer:
a) a = -g = 9.8 m/s²
, b) a = 0 m/s² and c) t1 = 0.0213 s
Explanation:
a) At the moment the marble is released its velocity is zero, so it has no resistance force, the only force acting is its weight, so the acceleration is the acceleration of gravity
a = -g = 9.8 m / s²
b) When the marble goes its terminal velocity all forces have been equalized, therefore, the sum of them is zero and consequently if acceleration is also zero
a = 0 m / s²
c) We have to assume a specific type of resistive force, for liquid in general the resistive force is proportional to the speed of the body.
The expression of this situation is
v = mg / b (1 -
)
For a very long time the exponential is zero, so the terminal velocity is
= mg / b
b = mg /
b = 5 10-3 9.8 / 0.3
b = 0.163
We already have all the data to calculate the time for v = ½
½ = (1 -)
½ = 1- e (- 0.163 t1 / 5 10-3)
e (-32.6 t1) = 1-0.5 (by ln())
-32.6 t1 = ln 0.5
t1 = -1 / 32.6 (-0.693)
t1 = 0.0213 s
For circular motion.
Centripetal acceleration = mv²/r = mω²r
Where v = linear velocity, r = radius = diameter/2 = 1/2 = 0.5m
m = mass = 175g = 0.175kg.
Angular speed, ω = Angle covered / time
= 2 revolutions / 1 second
= 2 * 2π radians / 1 second
= 4π radians / second
Centripetal Acceleration = mω²r = 0.175*(4π)² * 0.5 Use a calculator
≈13.817 m/s²
The magnitude of acceleration ≈13.817 m/s² and it is directed towards the center of rotation.
Tension in the string = m*a
= 0.175*13.817
= 2.418 N
Answer:
Explanation:
Given
volume of sample 
Temperature 
Pressure 
for different conditions
Temperature 
Pressure 
suppose 
is the volume of sample
Using ideal gas equation
For this problem, we use the conservation of momentum as a solution. Since momentum is mass times velocity, then,
m₁v₁ + m₂v₂ = m₁v₁' + m₂v₂'
where
v₁ and v₂ are initial velocities of cart A and B, respectively
v₁' and v₂' are final velocities of cart A and B, respectively
m₁ and m₂ are masses of cart A and B, respectively
(7 kg)(0 m/s) + (3 kg)(0 m/s) = (7 kg)(v₁') + (3 kg)(6 m/s)
Solving for v₁',
v₁' = -2.57 m/s
<em>Therefore, the speed of cart A is at 2.57 m/s at the direction opposite of cart B.</em>
Answer:
a) Focal length of the lens is 8 cm which is a convex lens
b) 6 cm
c) The lens is a convex lens and produces a virtual image which is upright and two times larger than the object.
Explanation:
u = Object distance = 4 cm
v = Image distance = -8 cm
f = Focal length
Lens Equation
a) Focal length of the lens is 8 cm which is a convex lens
Magnification
b) Height of image is 2×3 = 6 cm
Since magnification is positive the image upright
c) The lens is a convex lens and produces a virtual image which is upright and two times larger than the object.
