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3 years ago

PLEASE HURRY I HAVE 10 MINUTES LEFT ON MY TOPIC TEST

1 answer:

3 0

The answer is D.

Velocity is the speed in a particular direction.

Saying that you are going from Los Angeles to Catalina Island is not a particular direction, it is an end destination.

You might be interested in

1. What is the gravitational force between two 4 kilogram masses separated by a distance of 5

Anon25 [30]

Yo, I assumed that this situation occurs on Earth otherwise the answer would be different.

7 0

3 years ago

A square loop of wire with a small resistance is moved with constant speed from a field free region into a region of uniform B f

Misha Larkins [42]

Answer:

A) False

B) False

C) True

D) False

Explanation:

A) False, because when leaving the field, the coil experiences a magnetic force to the right.

B) When the loop is entering the field, the magnetic flux through it will increase. Thus, induced magnetic field will try to decrease the magnetic flux i.e. the induced magnetic field will be opposite to the applied magnetic field. The applied magnetic field is into the plane of figure and thus the induced magnetic field is out of the plane of figure. Due to that reason, the current would be counterclockwise. So the statement is false.

C) When the loop is leaving the field, the magnetic flux through the loop will decrease. Thus, induced magnetic field will try to increase the magnetic flux i.e. the inducued magnetic field will be in the same direction as the applied magnetic field. The applied magnetic field is into the plane of figure and thus the induced magnetic field is also into the plane of figure. Due to that reason, the current would be clockwise. So the statement is true.

D) False because when entering the field magnetic force will be toward left side

8 0

3 years ago

In class we calculated the range of a projectile launched on flat ground. Consider instead, a projectile is launched down-slope

zysi [14]

Answer:

With an initial speed of 10m/s at an angle 30° below the horizontal, and a height of 8m, the projectile travels 7.49m horizontally before it lands.

Explanation:

Since the horizontal motion is independent from the vertical motion, we can consider them separated. The horizonal motion has a constant speed, because there is no external forces in the horizontal axis. On the other hand, the vertical motion actually is affected by the gravitational force, so the projectile will be accelerated down with a magnitude $g$ .

If we have the initial velocity $v_o$ and its angle $\theta$ , we can obtain the vertical component of the velocity $v_{oy}$ using trigonometry:

$v_{oy}=v_osin\theta$

Therefore, if we know the height at which the projectile was launched, we can obtain the final velocity using the formula:

$v_{fy}^{2} =v_{oy}^{2}+2gy\\\\ v_{fy}=\sqrt{v_{oy}^{2}+2gy }$

Next, we compute the time the projectile lasts to reach the ground using the definition of acceleration:

$g=\frac{v_{fy}-v_{oy}}{\Delta t} \\\\\Delta t= \frac{v_{fy}-v_{oy}}{g}=\frac{\sqrt{v_{oy}^{2}+2gy} -v_{oy}}{g}$

Finally, from the equation of horizontal motion with constant speed, we have that:

$x=v_{ox}\Delta t= v_{ox}\frac{\sqrt{v_{oy}^{2}+2gy} -v_{oy}}{g}$

For example, if the projectile is launched at an angle 30° below the horizontal with an initial speed of 10m/s and a height 8m, we compute:

$v_{ox}=10\frac{m}{s} cos30=8.66\frac{m}{s}\\v_{oy}=10\frac{m}{s} sin30=5\frac{m}{s}\\\\x=8.66\frac{m}{s} \frac{\sqrt{(5\frac{m}{s}) ^{2}+2(9.8\frac{m}{s^{2}})8m}-5\frac{m}{s} }{9.8\frac{m}{s^{2} } } =7.49m$

In words, the projectile travels 7.49m horizontally before it lands.

8 0

4 years ago

If the height of the ramp is increased then the marble's speed will be greater because gravity will have less resistance when pu

11Alexandr11 [23.1K]

The dependent variable is height of ramp.

7 0

3 years ago

In order to slide a heavy desk across the floor at constant speed in a straight line, you have to exert a horizontal force of 80

notka56 [123]

The hint is "constant speed".
If there is a net force on an object, what occurs to that object? F net = m*a.... It accelerates!
So, if the desk is going at a CONSTANT speed, what does that tell you about the acceleration? There is a change in speed.
Fnet = m*a Since a = 0 Fnet = 0
Fnet = sum of the force... reflect the direction of F as the positive direction. Sum of the forces in the direction of F = 0 0 = F - friction F = friction
So, if F = 800 N, then friction = 800 N in the opposite direction.

8 0

3 years ago