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3 years ago

If a net force acting on a moving object causes its speed to increase, what

Physics

1 answer:

Klio2033 [76]3 years ago

7 0

Answer:

It increases.

Explanation:

If a force acts in the same direction as the object's motion, then the force speeds the object up. Either way, a force will change the velocity of an object. And if the velocity of the object is changed, then the momentum of the object is changed.

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What's saturns rotation

xeze [42]

The way it rotates is Counter-clockwise

4 0

4 years ago

She uses a voltmeter, that measures in volts, and an ammeter that measures in amps. Both were correctly placed in her circuit. I

Nesterboy [21]

Answer:

A) the ammeter is x

voltage across R₁ (left resistor) = 0.75 V

voltage across the right one = 0.3 V

C) 1.05 V

Explanation:

From the diagram attached below;

A) Assuming the homes were wired in series, and one of the homes face short circuit then all the houses would face power cut but it doesn't happen. So they must be connected in parallel.

Therefore; The ammeter is connected in series, Hence, the ammeter is x and the voltmeter must be z.

Given that:

x = 0.15 A

z = 0.3 V

Resistor (R) on the left = 5 ohms

Then, voltage across R₁ (left resistor) = 5×(x)

= 5×0.15

= 0.75 V

voltage across the right one = z = 0.3 V

The total voltage of battery = 0.75+0.3 = 1.05 V

6 0

3 years ago

A wheel initially spinning at wo = 50.0 rad/s comes to a halt in 20.0 seconds. Determine the constant angular acceleration and t

svetlana [45]

Answer:

(I). The angular acceleration and number of revolution are -2.5 rad/s² and 500 rad.

(II). The torque is 84.87 N-m.

Explanation:

Given that,

Initial spinning = 50.0 rad/s

Time = 20.0

Distance = 2.5 m

Mass of pole = 4 kg

Angle = 60°

We need to calculate the angular acceleration

Using formula of angular velocity

$\omega=-\alpha t$

$\alpha=-\dfrac{\omega}{t}$

$\alpha=-\dfrac{50.0}{20.0}$

$\alpha=-2.5\ rad/s^2$

The angular acceleration is -2.5 rad/s²

We need to calculate the number of revolution

Using angular equation of motion

$\theta=\omega_{0}t+\dfrac{1}{2}\alpha t$

Put the value into the formula

$\theta=50\times20-\dfrac{1}{2}\times2.5\times20^2$

$\theta=500\ rad$

The number of revolution is 500 rad.

(II). We need to calculate the torque

Using formula of torque

$\vec{\tau}=\vec{r}\times\vec{f}$

$\tau=r\times f\sin\theta$

Put the value into the formula

$\tau=2.5\times4\times 9.8\sin60$

$\tau=84.87\ N-m$

Hence, (I). The angular acceleration and number of revolution are -2.5 rad/s² and 500 rad.

(II). The torque is 84.87 N-m.

8 0

3 years ago

A student is holding a stone at a certain height. The stone has 50 joules of potential energy and 0 joules of kinetic energy. Th

Hitman42 [59]

Answer:

d) The stone will have about 50 joules of kinetic energy and 0 joules of potential energy .

Explanation:

Given :

Initial Potential energy , $P_i=50\ J$ .

Initial Kinetic energy , $K_i=0\ J$ . ( because ball is in rest )

Now , we know , kinetic energy is maximum when an object reaches ground .

Also , potential energy is zero when an object is in ground .

We know , by conservation of energy :

Initial total energy = Final total energy

$P_i+K_i=P_f+K_f\\\\50+0=0+K_f\\\\K_f=50 \ J$

Therefore , option d) is correct .

6 0

4 years ago

A string of mass 60.0 g and length 2.0 m is fixed at both ends and with 500 N in tension. a. If a wave is sent along this string

Darya [45]

Answer:

The speed of wave is $v_1 = 129.1 \ m/s$

The new speed of the two waves is $v = 129.1 \ m/s$

Explanation:

From the question we are told that

The mass of the string is $m = 60 \ g = 60 *10^{-3} \ kg$

The length is $l = 2.0 \ m$

The tension is $T = 500 \ N$

Now the velocity of the first wave is mathematically represented as

$v_1 = \sqrt{ \frac{T}{\mu} }$

Where $\mu$ is the linear density which is mathematically represented as

$\mu = \frac{m}{l}$

substituting values

$\mu = \frac{ 60 *10^{-3}}{2.0 }$

$\mu = 0.03\ kg/m$

$v_1 = \sqrt{ \frac{500}{0.03} }$

$v_1 = 129.1 \ m/s$

Now given that the Tension, mass and length are constant the velocity of the second wave will same as that of first wave (reference PHYS 1100 )

8 0

4 years ago