Which expression is equivalent to 5(2+7)? 0 2(5+7) O 2 + 7(5) O 5(2)+7 O 5(2)+5(7)

Provide an example of when momentum is conserved and explain your answer you can get 10 PTS if answered with a good explaination

dezoksy [38]

Answer:

$m_1=8\ kg,\ m_2=6\ kg,\ v_1=12\ m/s, v_2=4\ m/s,\ v_1'=-6\ m/s,\ v_2'=28\ m/s$

Explanation:

<u>Conservation of Momentum </u>

The total momentum of a system of two particles is

$p=m_1v_1+m_2v_2$

Where m1,m2,v1, and v2 are the respective masses and velocities of the particles at a given time. Then, the two particles collide and change their velocities to v1' and v2'. The final momentum is now

$p'=m_1v_1'+m_2v_2'$

The momentum is conserved if no external forces are acting on the system, thus

$m_1v_1+m_2v_2=m_1v_1'+m_2v_2'$

Let's put some numbers in the problem and say

$m_1=8\ kg,\ m_2=6\ kg,\ v_1=12\ m/s, v_2=4\ m/s,\ v_1'=-6\ m/s,\ v_2'=28\ m/s$

$(8)(12)+(6)(4)=(8)(-6)+(6)(28)$

$96+24=-48+168$

120=120

It means that when the particles collide, the first mass returns at 6 m/s and the second continues in the same direction at 28 m/s

4 0

3 years ago

A fan cart with the fan set to high rolled across the floor. The cart's speeds with the fan on high are shown below. If the fan

Vadim26 [7]

Answer:

Speed of cart's might be less than the high speed after 5 seconds.

Explanation:

Given that,

A fan cart with the fan set to high rolled across the floor.

Let the speed of fan cart with set to high is $x\ cm$ per second.

The fan supplies a force to the cart. If a lower fan speed were used, less force would be applied. This would cause a slower change in the cart's speed. So, the cart would be rolling more slowly than $x\ cm$ per second after 5 seconds. The speed of cart's might be less than $x\ cm$ per second.

Force is needed

A. for a moving object to keep moving at the same speed and direction

B. for a moving object to change its speed

C. for a motionless object to remain still

D. to prevent a moving object from turning

Hence,

Speed of cart's might be less than the high speed after 5 seconds.

3 0

3 years ago

On which factor potential energy depends?

Ludmilka [50]

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The potential energy of the object depends on

the height of the object with respect to some reference points,
the mass of the object,
the gravitational field the object is in.

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Hope it helps ~

3 0

2 years ago

Read 2 more answers

If a roller coaster cart, with a mass of 100 kg, traveled this coaster, how much kinetic energy would it have at point 'E'?

zzz [600]

Answer:

Explanation:

Assuming no friction between the roller coaster car and the hill, and neglecting air resistance, the kinetic energy the roller coaster car would have at the bottom of the hill would be equal to its gravitational potential energy at the top of the hill, by conservation of energy.

8 0

3 years ago

You have two windlasses (winches) named X and Y. Windlass X drum diameter is 50cm and windlass Y drum diameter is 75cm. Both are

Blababa [14]

You have two windlasses named X and Y. Windlass X drum diameter is 50cm and windlass Y drum diameter is 75cm. Both are hoisting a 50kg weight, Hence, X will lift faster and easier than Y

<h3>What is windlasses (winches) will lift faster?</h3>

Generally, the equation for the Torque is mathematically given as

Torque(X)=weight x radius of drum

T=50x9.81x0.25

T=122.625 Nm

For, Torque (Y)

T=50x9.81x0.375

T=183.93 Nm

Generally, the equation for the Equation of Power is mathematically given as

P= Torque * Angular velocity

Angular velocity (w)= 2 x pi x N/60

As a consequence, torque has an inverse relationship to speed. Because of this, the torque will decrease as the speed rises.

According to the previous statement, windlass X has a speed of lift that is at its maximum, but windlass Y has a speed that is very low.

Additionally, power is exactly proportional to torque, which means that the highest possible torque required the highest possible amount of energy and vice versa.

Therefore, X should raise at the highest possible speed while using the least amount of energy.

In conclusion, X will lift faster and easier than Y

Which expression is equivalent to 5(2+7)? 0 2(5+7) O 2 + 7(5) O 5(2)+7 O 5(2)+5(7)​

Which expression is equivalent to 5(2+7)? 0 2(5+7) O 2 + 7(5) O 5(2)+7 O 5(2)+5(7)