Given:
u(initial velocity): 154 m/s
accelerates (a): 1.8 m/s^2
t= 1 min=60 secs
Now we know that
s= ut + 1/2(at^2)
s= 154 x 60 + (1.8 × 60 ×60) ÷ 2
s= 12,480 m
Answer:
a) The initial speed of the rock is approximately 14.607 meters per second.
b) The greatest height of the rock from the base of the cliff is 42.878 meters.
Explanation:
a) The rock experiments a free-fall motion, that is a vertical uniform accelerated motion due to gravity, in which air friction and effects of Earth's rotation. By Principle of Energy Conservation we have the following model:
(Eq. 1)
Where:
, - Initial and final gravitational potential energies, measured in joules.
, - Initial and final translational kinetic energies, measured in joules.
By definitions of gravitational potential and translational kinetic energies we expand and simplify the equation above:
(Eq. 2)
Where:
- Gravitational acceleration, measured in meters per square second.
, - Initial and final height, measured in meters.
, - Initial and final speed of the rock, measured in meters per second.
If we know that , , and , then the equation is:
The initial speed of the rock is approximately 14.607 meters per second.
b) We use (Eq. 1) once again and if we know that , , and , then the equation is:
The greatest height of the rock from the base of the cliff is 42.878 meters.
Question:
A piece of soft iron is placed in a solenoid increasing the magnetic field in an arrangement that can be switched on and off. Such a device is called
Answer
a hysteresis loop.
an electrosolenoid.
a permanent magnet.
a ferromagnet.
an electromagnet
Answer:
A piece of soft iron is placed in a solenoid increasing the magnetic field in an arrangement that can be switched on and off. Such a device is called an electromagnet.
Explanation:
When a magnet is processed by supplying electricity than it is called as electromagnet and therefore its strength can be fluctuated as dependent on amount of electricity supplied.
Here, when a iron piece is moved closer to a long coil of wire named solenoid physical interaction named electromagnetic force take place between two electrically charged particles.
This force is supplied by electromagnetic fields constructed from electric and magnetic field. This is also called as Lorentz force constituted from both electricity and magnetism. This property itself gives evidence of characteristics of material used for electromagnetism.
Answer:
Explanation:
Given data
Electric Field E=2.5×10⁵ N/C
To find
Charge Density
Solution
From definition of charge density we know that:
Charge Density=Electric field×Permttivity
Where Permttivity ∈₀=8.85×10⁻¹²C²/N.m²
B. John is correct, but Linda is wrong
C. John is wrong, but Linda is correct
D. They are both correct.
E. John must be wrong, because Linda always wins these arguments.
Answer:
They are both correct.
Explanation:
The density of an object is defined as the ratio of its mass to its volume. This implies that the density of the object is both proportional to the mass and also to the volume of the object. John only mentioned mass which is correct. Linda mentioned the second variable on which density depends which is the volume of the object.
Hence considering the both statements objectively, one can say that they are both correct.
To solve this problem it is necessary to apply the related concepts to the moment of inertia in a disk, the conservation of angular momentum and the kinematic energy equations for rotational movement.
PART A) By definition we know that the moment of inertia of a disk is given by the equation
Where
M = Mass of the disk
R = Radius
Replacing with our values we have
The initial angular momentum then will be given as
Therefore the total moment of inertia of the table and the disc will be
The angular velocity at the end point will be given through the conservation of the angular momentum for which it is understood that the proportion of inertia and angular velocity must be preserved. So
Therefore the new angular velocity is 1.15rad/s
PART B) Through the conservation of rotational kinetic energy we can identify that its total change is subject to
Therefore the change in kinetic energy is 0.034J
Given the wavelength and the frequency, the speed of the wave can be calculated by multiplying these two values. Substituting the given values, the speed of the wave is found to be 0.80 m/s.
In this problem, we are given the wavelength (distance between two crests) as 1.20 m and the frequency, indirectly given as the number of crests passing a certain point per time. We are told that 8 crests pass the point every 12 seconds, this means there were 8 complete cycles in this time. Therefore, the frequency (number of cycles per second) is A/B = 8 cycles /12 s = 0.67 Hz.
The speed of a wave is given by the equation v = fλ, where v is the wave speed, f is the frequency, and λ is the wavelength. If we substitute the given values into the formula we get: v = 0.67 Hz * 1.20 m = 0.80 m/s. Hence, the speed of the wave is 0.80 m/s.
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