A ball with a mass of 170 g which contains 3.80×108 excess electrons is dropped into a vertical shaft with a height of 145 m . At the bottom of the shaft, the ball suddenly enters a uniform horizontal magnetic field that has a magnitude of 0.250 T and direction from east to west.A)If air resistance is negligibly small, find the magnitude of the force that this magnetic field exerts on the ball just as it enters the field.
Use 1.602×10−19 C for the magnitude of the charge on an electron.
B)Find the direction of the force that this magnetic field exerts on the ball just as it enters the field.
a-from north to south
b-from south to north
B. south - north
A) We use the Lorentz force
F = qv X B
|F| = qvB
to calculate the magnitude of the force we need the speed of the of the ball.
and by replacing in the formula for the magnitude of the force we have (taking into account the excess of electrons)
A water-skier is being pulled by a tow rope attached to a boat. As the driver pushes the throttle forward, the skier accelerates. A 76.2-kg water-skier has an initial speed of 5.0 m/s. Later, the speed increases to 10.4 m/s. Determine the work done by the net external force acting on the skier.
Work done will be equal to 3186.396 J
We have mass m = 76.2 kg
Initial velocity u = 5 m/sec
Final velocity v = 10.4 m/sec
We have to find the work done
From work energy theorem work done is equal to change in kinetic energy
w = 3168.396 J
So work done will be equal to 3186.396 J
An advantage of J.J. Thomson's Plum Pudding Model was that it _____. A. was a much less expensive way to study atoms B. simplified the calculations necessary to describe an atom C. clearly explained where electrons were located in an atom D. is much less expensive to bake a plum pudding than to look at an atom
the answer is d i think
Answer: plz mark brainliest
the answer is C
bc he used the plums or whatever's inside of the pudding to identify were electrons could be located and since it was a well known deserte many people where able to understand his analogy
A train is traveling at 30.0 m/sm/s relative to the ground in still air. The frequency of the note emitted by the train whistle is 262 HzHz. The speed of sound in air should be taken as 344 m/sm/s.A. What frequency fapproach is heard by a passenger on a train moving at a speed of 18.0 m/s relative to the ground in a direction opposite to the first train and approaching it?B. What frequency frecede is heard by a passenger on a train moving at a speed of 18.0 m/s relative to the ground in a direction opposite to the first train and receding from it?
speed of sound = 344 m/s
speed of train = 30 m/s
frequency emitted by the train = 262 Hz
f_L is the frequency of listener
f_S is the frequency of the source of the sound
v is the speed of the sound
v_L is the speed of listener.
v_S is the speed of the source
a) Speed of the passenger in another train , v = 18 m/s
another train is moving in opposite direction and approaching
v_L is positive as the listener is moving forward.
v_S is negative at the source is moving toward the listener.
b) Speed of the passenger in another train , v = 18 m/s
another train is moving in opposite direction and receding
v_L is negative as the listener is moving away from source.
v_S is positive at the source is moving away the listener.
A boat can travel in still water at 56 m/s. If the boats sails directly across a river that flows at 126 m/s. What is the boats speed relative to the ground
The answer is below
The speed of the boat in still water is perpendicular to the speed of the water flow. Therefore the speed relative to the ground (V), the speed of flow and the speed of the boat in still water form a right angled triangle. Hence the speed relative to the ground is given as:
V² = 56² + 126²
V² = 19012
V = 137.9 m/s
The ____ contains the highest concentration of ozone
I believe the term you are looking for is the ozone layer. This layer is in the highest region if the stratosphere.
Suppose that a solid ball, a solid disk, and a hoop all have the same mass and the same radius. Each object is set rolling without slipping up an incline with the same initial linear (translational) speed. Which object goes farthest up the incline?
Given the same initial linear speed, a solid ball, solid disk, and hoop will expend energy on both rotation and translation. The solid ball, having the lowest moment of inertia, uses the most energy for translation and, therefore, will travel the highest up an incline.
In the context of this problem related to physics, the deciding factor is the distribution of mass, which influences each object's moment of inertia. Objects set to roll tend to use energy in two ways: translation (moving along the incline) and rotation (spinning about their center). Moment of inertia essentially measures how much of the object's energy goes towards rotation.
For a solid ball, solid disk, and hoop with the same mass and radius, the hoop has the highest moment of inertia with all of its mass at the maximum distance from the center. Followed by the solid disk, with its mass spread evenly from the center to its edge. Lastly, the solid ball has the lowest moment of inertia as its mass is concentrated towards the center.
This means that, given the same initial linear speed, the hoop will expend most of its energy on rotation rather than moving up the incline (translation). The solid disk will have a more balanced distribution between translation and rotation, and finally, the solid ball will use the least amount of energy on rotation and the most on translation. As such, the solid ball will go the farthest up the incline.
Learn more about the Physics of Rotating Objects here: