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2 years ago

A woman can row her canoe at 2.5 m/s. If she faces an opposing current of 3.0 m/s, how fast will she go forward?

Physics

1 answer:

taurus [48]2 years ago

8 0

Answer:

V = - 0.5 [m/s]

Explanation:

In order to solve this problem, we must use the principle of relative speeds. This is for an observer who is on the edge of the river he can see how the river moves to the left and the woman tries to move to the right but can not since:

$V_{total}=-3+2.5\\V_{total}=-0.5 [m/s]$

That is, the person sees how the woman moves to the left but with avelocity of 0.5 [m/s] to the left

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For a 1 efficient step down transformer voltage in primary and secondary are equal current in primary and secondary are equal in

Fynjy0 [20]

The given condition for a 100% efficient step down transformer is not true.

<h3>How do Step-down Transformers work?</h3>

Because there are fewer turns in the secondary winding of a step-down transformer, the secondary voltage is lower than the initial voltage. As a result, this kind of transformer is employed to reduce the voltage to the levels intended for the circuit. Almost all power supply incorporate a step-down transformer to keep the operating voltage range of the circuit within acceptable limits. Electronic transformers and distribution systems are often where these transformers are installed (power transformers).

<h3>What Does a Step-Down Transformer Mean by Power?</h3>

Using the system voltage and current, we can calculate the power of a transformer. Volt-Amps, or VA, is the unit used to measure the power in a transformer (for larger transformers Kilo Volt-Amps, kVA).

Any transformer should, in theory, have constant power on both sides, which implies that the power available on the secondary side of the transformer should match the power available on the primary side. This also applies to step-down transformers. A step-down transformer's secondary side has a lower voltage than its primary side, hence in order to balance the transformer's total power, the secondary current would need to be increased.

<h3>What is the Step-Down Transformer's Relationship Between Voltage and Current?</h3>

In a step-down transformer, the output current is greater than the input current while the output voltage is lower than the primary voltage.

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2 years ago

Types of RM radiation that make up the electromagnetic spectrum are microwaves, infrared light, ultraviolet light, X-rays, and g

HACTEHA [7]

Answer:

True

Explanation:

The electromagnetic spectrum can be regarded as term that give description of range of light that are in existence, and this range from radio waves up to gamma rays. It can be explained as

range of frequencies that electromagnetic radiation takes with thier respective wavelengths as well as photon energies

The Types of electromagnetic radiation that make up the electromagnetic spectrum are

✓ microwaves

✓ infrared light

✓ ultraviolet light

✓X-rays,

✓gamma rays.

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3 years ago

A student connects a 1 hp motor to a bicycle. How much time will it take for the bicycle to accelerate from rest to a speed of 5

bija089 [108]

Answer:

t=2s

Explanation:

The definition of power is:

$P=\frac{W}{t}$

And the work-energy theorem states that:

$W=\Delta K$

Since the movement starts from rest, we have that:

$\Delta K=\frac{mv_f^2}{2}-\frac{mv_0^2}{2}=\frac{mv_f^2}{2}$

And putting all together:

$P=\frac{mv_f^2}{2t}$

Since we want the time taken:

$t=\frac{mv_f^2}{2P}$

Which for our values is:

$t=\frac{(120kg)(5m/s)^2}{2(746W)}=2s$

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3 years ago

Read 2 more answers

A diver springs upward from a board that is 4.40 m above the water. At the instant she contacts the water her speed is 13.5 m/s

Yakvenalex [24]

The diver has the initial velocity, both (a) magnitude is 9.8 m/s and (b) direction is 73.5°.

<h3>What is free falling?</h3>

When an object is released from rest in free air considering no friction, the motion is depend only on the acceleration due to gravity, g.

If we drop an object of mass m near the Earth surface from a height h, it has initial mechanical energy(P.E)

U =mgh

When the object strikes the ground, all the potential energy converted into kinetic energy.

K.E = 1/2mv²

where v is the speed just before hitting the ground.

A diver springs upward from a board that is 4.40 m above the water. At the instant, she contacts the water her speed is 13.5 m/s and her body makes an angle of 78.1 ° with respect to the horizontal surface of the water.

(a)

From energy conservation principle, initial and final mechanical energy are equal.

1/2mu² + mgh = 1/2mv²

where, u is the initial velocity of the diver.

u = sq rt (v² - 2gh)

u = sq rt (13.5² - 2x9.81x4.4)

u = 9.798 m/s or 9.8 m/s

Thus, the velocity of the diver is 9.8 m/s.

(b)

The horizontal component of velocity will remain constant.

The horizontal component of acceleration is zero.

Then,

ucosθ = vcosΦ

θ = cos⁻¹ [ (13.5 x cos 78.1)/9.8 ]

θ = 73.5°

Thus, the direction of velocity is 73.5°.

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1 year ago

According to Archimedes' Principle, what condition has to be met for an object to float?you will get branliest

MissTica

Explanation:

The buoyant force must be greater to float, otherwise it would sink, its like a barrel in water, the more water weight in it the more it sinks, the more air weight the more it rises.

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2 years ago