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3 years ago

Hanna tosses a ball straight up with enough speed to remain in the air for several seconds?

Physics

2 answers:

olga_2 [115]3 years ago

3 0

A) the velocity is 0 m/s

Lorico [155]3 years ago

3 0

Answer:

Explanation:

In the free fall motion we have that the acceleration is constant and produced by gravity, this acceleration has a magnitude of 32 ft/s2 or 9.8 m/s2 depending on the units you are working with. This means that every second the speed changes a magnitude of 32 ft/2, the velocity will depend of whether the ball is going upward (positive) or downward (negative).

A) At the highest point the ball stops to start the descend, here v=0 ft/s

B) +32 ft/s. The vector is going up, in the next second the velocity is going to be 0 (negative acceleration)

C) V=vf-vo=0-32=-32 ft/s is the constant change in velocity in projectile motion

D) -32 ft/s. The vector is pointing downward

E) V=vf-vo=-32-0=-32 ft/s is the constant change in velocity in projectile motion, 32 ft/s per second

F) Delta V=vf-vo=-32-32=-72 ft/s

g) gravity acceleration is constant 32 ft/s2 (pointing downward vector)

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Can someone plzzzz help with these 3 I don’t understand

Aleks [24]

12.) Active transport because the cell must use energy to move large particles across the membrane.

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14.) In cells with a nucleus, as in eukaryotes, the cell cycle is also divided into two main stages: interphase and the mitotic (M) phase (including mitosis and cytokinesis). During interphase, the cell grows, accumulating nutrients needed for mitosis, and undergoes DNA replication preparing it for cell division.

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3 years ago

If an oscillating mass has a frequency of 1.25 Hz, it makes 100 oscillations in

KatRina [158]

Answer:

Time, t = 80 seconds

Explanation:

Given that,

The frequency of the oscillating mass, f = 1.25 Hz

Number of oscillations, n = 100

We need to find the time in which it makes 100 oscillations. We know that the frequency of an object is number of oscillations per unit time. It is given by :

$f=\dfrac{n}{t}$

$t=\dfrac{n}{f}$

$t=\dfrac{100}{1.25\ Hz}$

t = 80 seconds

So, it will make 100 oscillations in 80 seconds. Hence, this is the required solution.

4 0

2 years ago

A particular planet has a moment of inertia of 9.74 × 1037 kg ⋅ m2 and a mass of 5.98 × 1024 kg. Based on these values, what is

malfutka [58]

Answer: A) $6.38(10)^{6} m$

Explanation:

The equation for the moment of inertia $I$ of a sphere is:

$I=\frac{2}{5}mr^{2}$ (1)

Where:

$I=9.74(10)^{37}kg m^{2}$ is the moment of inertia of the planet (assumed with the shape of a sphere)

$m=5.98(10)^{24}kg$ is the mass of the planet

$r$ is the radius of the planet

Isolating $r$ from (1):

$r=\sqrt{\frac{5I}{2m}}$ (2)

Solving:

$r=\sqrt{\frac{5(9.74(10)^{37}kg m^{2})}{2(5.98(10)^{24}kg)}}$ (3)

Finally:

$r=6381149.077m \approx 6.38(10)^{6} m$

Therefore, the correct option is A.

4 0

2 years ago

A man pushes a shopping cart across a level floor. What force resists the effort force? A) gravity B) friction C) the normal for

Kipish [7]

Answer:

B) Friction

Explanation:

Friction is a force that acts when an object is sliding along a surface. Microscopically, this force is due to the fact that the two surfaces are not perfectly smooth, but they have "imperfections" that cause a force that opposes the motion of the object.

For an object sliding on a flat surface, the force of friction has magnitude:

$F_f = \mu_k mg$

where

$\mu_k$ is the coefficient of kinetic friction

m is the mass of the object

g is the acceleration of gravity

The direction of the force of friction is always opposite to the direction of motion of the object.

In reality, friction also acts if the object is at rest and it is pushed by a force; in this case, we talk about static friction, and its magnitude is

$F_f = \mu_s mg$

where $\mu_s$ is called coefficient of static friction, and it is generally larger than the coefficient of kinetic friction.

8 0

2 years ago

The state of a medium affect the speed of sound

fenix001 [56]

Answer:

no it can not effect the speed of sound not shure tho

5 0

2 years ago