Freight trains can produce only relatively small acceleration and decelerations. (a) what is the final velocity (in m/s) of a freight train that accelerates at a rate of 0.0400 m/s2 for 8.00 min, starting with an initial velocity of 3.00 m/s? 22.2 correct: your answer is correct. m/s (b) if the train can slow down at a rate of 0.550 m/s2, how long (in s) will it take to come to a stop from this velocity? incorrect: your answer is incorrect. s (c) how far (in m) will it travel in each case?

Answer

Initial velocity of the freight train = V₁ = 3 m/s

Acceleration of the freight train = a₁ = 0.04 m/s²

Time period the freight train accelerates for = T₁

                                                                         = 8 min = 480 sec

Velocity of the freight train after accelerating for 8 min = V₂

V₂ = V₁ + a₁T₁

V₂ = 3 + (0.04)(480)

V₂ = 22.2 m/s

Distance traveled by the freight train while accelerating = D₁

D₁ = V₁T₁ + 0.5× a₁T₁²

D₁ = (3)(480) + 0.5×(0.04)(480)²

D₁ =6048

Deceleration of the freight train = a₂ = -0.55 m/s²

Final velocity of the freight train = V₃ = 0 m/s (Comes to a stop)

Time taken by the freight train to come to a stop = T₂

V₃ = V₂ + a₂T₂

0 = 22.2 + (-0.55)T₂

T₂ = 40.36 sec

Distance traveled by the freight train during deceleration = D₂

D₂ = V₂T₂ + 0.5a₂T₂²

D₂ = (22.2)(40.36) +0.5 (-0.55)(40.36)²

D₂ = 448.04 m

answer: the correct answer is 1.

explanation: there are various process in which a radioactive nuclei decays:

1) alpha decay: in this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. the mass number is reduced by 4 units.

2) electron capture: in this decay process, a parent nuclei absorbs an electron and gets converted into a neutron. simply, a proton and an electron combines together to form a neutron. mass number does not change in this process.

3) gamma ray emission: it is a decay process in which an unstable nuclei gives excess energy by a spontaneous electromagnetic process. this decay releases . this process does not change the mass number.

4) positron emission: it is a type of decay process, in which a proton gets converted to neutron and an electron neutrino. this is also known as -decay. in this the mass number remains same.

from the above information, we see that only alpha-decay is producing a change in the mass number of the nucleus.

the electric field is a “force field” around a charged object that illustrates the direction the electric force would push an imaginary