5. Which pair of words, in order, correctly completes

A 1 170.0 kg car traveling initially with a speed of 25.000 m/s in an easterly direction crashes into the back of a 9 800.0 kg t

Stella [2.4K]

Answer:

Explanation:

mass of car, m1 = 1170 kg

mass of truck, m2 = 9800 kg

initial velocity of car, u1 = 25 m/s

initial velocity of truck, u2 = 20 m/s

final velocity of car, v1 = 18 m/s

Let the final velocity of truck is v2.

(a) Use the conservation of momentum

m1 x u1 + m2 x u2 + m1 x v1 + m2 x v2

1170 x 25 + 9800 x 20 = 1170 x 18 + 9800 x v2

29250 + 196000 = 21060 + 9800 v2

v2 = 20.84 m/s

(b) Total kinetic energy before collision,

Ki = 0.5 x 1170 x 25 x 25 + 0.5 x 9800 x 20 x 20

Ki = 365625 + 1960000 = 2325625 J

Total final kinetic energy

Kf = 0.5 x 1170 x 18 x 18 + 0.5 x 9800 x 20.84 x 20.84

Kf = 189540 + 2128097.44

Kf = 2317637.44 J

Change in energy = 2325625 - 2317637.44 = 7987.56 J

(c) It is due to the heat energy

4 0

4 years ago

Why would a person who weighs 100 lbs. on Earth weigh significantly more on Ju-piter?

Nitella [24]

Answer:

Is a

Explanation:

8 0

3 years ago

Which of the statements below describes how a motor operates

uranmaximum [27]

Answer:

need Read this excerpt from "Not a Dove, But No Longer a Hawk."

Despite these misgivings, I do not see how we can do anything but continue to prosecute the war. We can and should limit the violence and the suffering being inflicted on the civilians as much as possible, but for whatever reasons, successive Administrations in Washington have carried the commitment in Vietnam to the point where it would be very difficult to prevent any precipitate retreat from degenerating into a rout. If the United States were to disengage from Vietnam under adverse conditions, I believe that the resulting political and psychological shockwaves might undermine our entire position in Southeast Asia.

Which statement best describes the paradox in this excerpt?

The author acknowledges that civilians should not suffer, but states that the civilians must retreat.

The author suggests that the administrators in Washington are busy making policies while overlooking the need to end the war.

The author acknowledges that the violence should stop, but admits that a retreat might have dire consequences.

The author suggests that the Vietnamese people are counting on US support, though their political ideals are not democratic.

Explanation:

7 0

3 years ago

Which of the following statements correctly describe the various applications listed above?

fgiga [73]

Answer:

The answer is "c,d,e, and g".

Explanation:

The correct choices can be defined as follows:

Higher-frequency microwaves aren't used in any of these systems.
Infrared waves aren't seen in each of these technologies.
Its shortest wavelength of all of the technologies listed is the above radiation generated by certain wireless networks.
These devices all produce waves of wavelengths ranging from 0.10 to 10.0 cm.

3 0

3 years ago

A greyhound's velocity changes from rest to 19 m/s in 2 seconds. What is the greyhound's average acceleration?

Andrew [12]

It should be b)9.5m/s2

6 0

3 years ago