PLEASE HELP!!! When you lift a book from the ground to your desk, what kind of work do you do, negative or positive? By lifting
1 answer:
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Answer:
The frequency is 302.05 Hz.
Explanation:
Given that,
Speed = 18.0 m/s
Suppose a train is traveling at 30.0 m/s relative to the ground in still air. The frequency of the note emitted by the train whistle is 262 Hz .
We need to calculate the frequency
Using formula of frequency
Where, f = frequency
v = speed of sound
= speed of passenger
= speed of source
Put the value into the formula
Hence, The frequency is 302.05 Hz.
Explanation:
We have,
Speed of plane a is 900 km/h
Plane b is moving at a rate of
It is required to find which plane is faster. To find which plane is faster, we need to compare their speeds.
Speed of a plane a is 900 km/h and that of plane b is 50 km/h. So, we can say that plane a is moving faster.
Answer:
a) see attached, a = g sin θ
b)
c) v = √(2gL (1-cos θ))
Explanation:
In the attached we can see the forces on the sphere, which are the attention of the bar that is perpendicular to the movement and the weight of the sphere that is vertical at all times. To solve this problem, a reference system is created with one axis parallel to the bar and the other perpendicular to the rod, the weight of decomposing in this reference system and the linear acceleration is given by
Wₓ = m a
W sin θ = m a
a = g sin θ
b) The diagram is the same, the only thing that changes is the angle that is less
θ' = 9/2 θ
c) At this point the weight and the force of the bar are in the same line of action, so that at linear acceleration it is zero, even when the pendulum has velocity v, so it follows its path.
The easiest way to find linear speed is to use conservation of energy
Highest point
Em₀ = mg h = mg L (1-cos tea)
Lowest point
Emf = K = ½ m v²
Em₀ = Emf
g L (1-cos θ) = v² / 2
v = √(2gL (1-cos θ))
