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olga2289 [7]
3 years ago
14

If a speeding train hits the brakes and it takes the train 39 seconds to go from 54.8 m/s to 12 m/s what is the acceleration?

Physics
2 answers:
jekas [21]3 years ago
8 0

Answer:

-1.09m/sec^2

Explanation:

Acceleration= (Vf-Vi)/Time

=12-54.8

= -42.8

= -42.8/39

=-1.09

-ve sign is due to recoil of train

as it suddenly hits brakes.

user100 [1]3 years ago
6 0

Answer:1.097 m/s^2

Explanation:

a=(final velocity- initial velocity )/time

=(54.8-12)/39

=1.097 m/s^2

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Answer:

Many types of scientific equipment are used to perform different functions in the science lab. Which of the following combinations of equipment would be needed to bring one liter of water to 85°C? a. ... Various pieces of safety equipment are used in the lab to provide protection against injury.

Explanation:

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A stationary speed gun emits a microwave beam at 2.10*10^10Hz. It reflects off a car and returns 1030 Hz higher. What is the spe
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Answer: V = 15 m/s

Explanation:

As  stationary speed gun emits a microwave beam at 2.10*10^10Hz. It reflects off a car and returns 1030 Hz higher. The observed frequency the car will be experiencing will be addition of the two frequency. That is,

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Using doppler effect formula

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2.100000103×10^10 = 3×10^8/(3×10^8 -V) × 2.1×10^10

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Cross multiply

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The work done by the normal force n when the box slides down a frictionless incline and gaining speed is zero.

<h3>What is normal force?</h3>

The force of contact is called the normal force. When the two surfaces are in contact with each other, then the normal force acts.

This force is applied by the solid bodies on each other in order to prevent the passing through each other.

A box slides down a frictionless incline, gaining speed. For this box, the value of work done by normal force has to be found out. Let's analyze the given condition.

  • The body is gaining the speed, which means there is a change in kinetic energy.
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Thus, the work done by the normal force n when the box slides down a frictionless incline and gaining speed is zero.

Learn more about the normal force here;

brainly.com/question/10941832

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