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3 years ago

A box is pushed horizontally with constant speed across a rough horizontal surface. Which of the following must be true?

1 answer:

5 0

D

Because if an object is moving at a constant speed the force of friction must equal the applied (horizontal) force, and for it to be accelerating or decelerating, the force of friction and the applied force must be unequal

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What can a human still do better and faster than any machine learning solution<br>

emmasim [6.3K]

Answer:

mistakes I guess lol don't take serious

3 0

3 years ago

Mike is standing on the roof of a building looking at the roof of the neighboring building that is 15 meters away and 10 meters

amid [387]

Answer:

Part a)

$t = 1.65 s$

Part b)

$x = 40.4 m$

Since the distance of other building is 15 m so YES it can make it to other building

Part c)

$v = 27.3 m/s$

direction of velocity is given as

$[tex]\theta = 26.35 degree$

Explanation:

Part a)

acceleration due to gravity on this planet is 3/4 times the gravity on earth

So the acceleration due to gravity on this new planet is given as

$a = \frac{3}{4}(9.81)$

$a = 7.36 m/s^2$

now the vertical displacement covered by the canister is given as

$y = 10 m$

now by kinematics we have

$y = \frac{1}{2}gt^2$

$10 = \frac{1}{2}(7.36)t^2$

$t = 1.65 s$

Part b)

Horizontal speed of the canister is given as

$v_x = 24.5 m/s$

now the distance moved by it

$x = v_x t$

$x = 24.5 (1.65)$

$x = 40.4 m$

Since the distance of other building is 15 m so YES it can make it to other building

Part c)

Final velocity in X direction will remains the same

$v_x = 24.5 m/s$

final velocity in Y direction

$v_y = v_i + at$

$v_y = 0 + (7.36)(1.65)$

$v_y = 12.14 m/s$

now magnitude of velocity is given as

$v = \sqrt{v_x^2 + v_y^2}$

$v = \sqrt{24.5^2 + 12.14^2}$

$v = 27.3 m/s$

direction of velocity is given as

$\theta = tan^{-1}\frac{v_y}{v_x}$

$\theta = tan^{-1}\frac{12.14}{24.5}$

$[tex]\theta = 26.35 degree$

6 0

3 years ago

In a series RLC ac circuit, a second resistor is connected in series with the resistor previously in the circuit. As a result of

AnnyKZ [126]

Answer:

* The first thing we observe is that the frequency response does not change

* The current that circulates in the circuit decreases due to the new resistance at the resonance point,

Z = R + R₂

Explanation:

The impedance of a series circuit is

Z₀² = R² + (X_L-X_C) ²

when we place another resistor in series the initial resistance impedance changes to

Z² = (R + R₂) ² + (X_L - X_C) ²

let's analyze this expression

* The first thing we observe is that the frequency response does not change

* The current that circulates in the circuit decreases due to the new resistance at the resonance point,

Z = R + R₂

8 0

3 years ago

Calculate the east component of a resultant 32.5 m/s, 35.0° east of north.

ValentinkaMS [17]

Answer:

East component is: 18.64 m/s

Explanation:

If the resultant is 32.5 m/s directed 35 degrees east of north, then we use the sin(35) projection to find the east component of the velocity:

East component = 32.5 m/s * sin(35) = 18.64 m/s

4 0

3 years ago

A water pump pumps 3 kg of water every second from the bottom of a well to the top of the well 50 m above if the pump used 2000

vesna_86 [32]

watts = work per second.

work is mgh = 3x10x50=1500

watts out = 1500

Watts used = 2000

eff=1500/2000=75%

8 0

3 years ago