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A planet orbits a star in an elliptical orbit. At a particular instant the momentum of the planet is (-2.6×1029,-1.0×1029,0)kg.m/s, and the force on the planet by the star is (-2.5×1022,-1.4×1023,0)N. Find F∥and F⊥.

Short Answer

Expert verified

-6.87×1022,-2.64×1022,0Nand4.37×1022,-1.13×1023,0N

Step by step solution

01

Identification of the given data 

The given data is listed below as,

  • The planet’s momentum is, p=-2.6×1029,-1.0×1029,0kg.m/s.

  • The force exerted on the planet is, F=-2.5×1022,-1.4×1023,0N.

02

Significance of the parallel force

The parallel force mainly acts in the same or the opposite direction at some points of an object.

From the momentum principle, the equation of the parallel component of the force is expressed as,

F=Fcosθp^ …(1)

Here, F∥is the parallel force, Fis the absolute value of the gravitational force, p^is the unit vector, and θ{"x":[[211.633056640625,208.7886962890625,205.2332763671875,199.5445556640625,198.12237548828125,195.27801513671875,194.56695556640625,195.9891357421875,197.4112548828125,202.388916015625,207.366455078125,213.766357421875,218.0328369140625,227.988037109375,237.943359375,249.3206787109375,253.5872802734375,263.54248046875,272.0755615234375,276.342041015625,280.6085205078125,282.03076171875,285.586181640625,287.719482421875,290.5638427734375,291.27490234375,291.9859619140625,292.697021484375,292.697021484375,292.697021484375,291.27490234375,290.5638427734375,289.1416015625,288.4305419921875,286.2972412109375,284.1640625,281.3197021484375,280.6085205078125,278.475341796875,275.6309814453125,272.78662109375,271.3643798828125,267.097900390625,263.54248046875,258.5648193359375,255.0093994140625,249.3206787109375,242.9208984375,237.232177734375,233.6767578125,227.988037109375,222.29931640625,218.743896484375,215.1884765625,213.766357421875,208.7886962890625,208.07763671875,205.9443359375,204.522216796875,203.0999755859375,200.96673583984375,200.255615234375,200.255615234375,200.255615234375,200.255615234375,200.96673583984375,202.388916015625,204.522216796875,206.6553955078125,208.7886962890625,210.2108154296875,215.8995361328125,218.743896484375,223.010498046875,225.1436767578125,229.4102783203125,233.6767578125,237.943359375,240.0765380859375,242.9208984375,245.7652587890625,247.8985595703125,248.609619140625,250.742919921875,252.8760986328125,254.29833984375,257.1427001953125,258.5648193359375,260.6981201171875,263.54248046875,264.2535400390625,265.67578125,267.097900390625,268.5201416015625,269.231201171875,269.9422607421875,270.6533203125,271.3643798828125,272.0755615234375,272.78662109375,272.78662109375,273.4976806640625,274.208740234375,274.208740234375,274.919921875,274.919921875,275.6309814453125,275.6309814453125,276.342041015625,276.342041015625,277.0531005859375,277.0531005859375,277.7642822265625]],"y":[[54.451416015625,65.10821533203125,75.7650146484375,90.68453979492188,97.07861328125,109.15631103515625,121.2340087890625,132.60125732421875,137.574462890625,146.09991455078125,155.3358154296875,161.7298583984375,164.5716552734375,168.83441162109375,170.96575927734375,171.67620849609375,170.96575927734375,169.54486083984375,167.41351318359375,165.28216552734375,161.0194091796875,159.5985107421875,153.91485595703125,148.94171142578125,142.547607421875,138.995361328125,130.46990966796875,122.65496826171875,115.5504150390625,111.9981689453125,104.18316650390625,96.3681640625,89.26364135742188,86.42181396484375,80.02774047851562,75.0545654296875,70.08139038085938,67.23959350585938,64.39776611328125,60.84552001953125,57.293243408203125,55.872344970703125,53.030517578125,50.899169921875,48.767791748046875,48.057342529296875,47.346893310546875,47.346893310546875,48.057342529296875,48.767791748046875,50.899169921875,53.030517578125,55.161865234375,58.003692626953125,59.424591064453125,62.97686767578125,66.52914428710938,70.79183959960938,72.9232177734375,77.18594360351562,83.58001708984375,87.84274291992188,89.97409057617188,94.947265625,99.2099609375,101.34136962890625,105.60406494140625,108.44586181640625,111.9981689453125,114.8399658203125,116.2608642578125,119.1026611328125,120.5235595703125,121.9444580078125,121.9444580078125,121.9444580078125,121.2340087890625,119.8131103515625,119.1026611328125,118.3922119140625,116.9713134765625,116.2608642578125,115.5504150390625,114.8399658203125,113.4190673828125,111.9981689453125,110.57720947265625,109.86676025390625,107.73541259765625,106.31451416015625,104.89361572265625,104.18316650390625,102.76226806640625,102.05181884765625,100.630859375,100.630859375,99.92041015625,99.2099609375,98.49951171875,97.7890625,97.07861328125,96.3681640625,95.65771484375,94.947265625,94.947265625,94.23681640625,93.5263671875,92.81588745117188,92.10543823242188,91.39498901367188,90.68453979492188,89.97409057617188,88.55319213867188]],"t":[[0,116,133,149,166,183,199,216,233,250,266,283,299,316,333,350,367,383,399,416,433,450,466,483,500,517,533,550,566,583,600,616,633,650,666,683,700,716,733,750,766,783,800,816,833,850,867,883,900,917,933,950,966,984,1000,1017,1033,1050,1067,1083,1100,1117,1133,1150,1166,1183,1200,1217,1233,1250,1267,1284,1300,1317,1334,1350,1367,1383,1400,1417,1433,1450,1467,1483,1500,1517,1534,1550,1567,1583,1600,1617,1634,1650,1667,1684,1700,1717,1733,1767,1784,1800,1818,1850,1867,1884,1901,1924,1951,1984,2000,2018,2050]],"version":"2.0.0"}is the angle between the momentum and gravitational force.

03

Determination of the parallel force of the planet

The magnitude of the momentum of the planet can be expressed as,

p=p2x+p2y+p2z

Here, px,py, and pzare the momentum at the x, yand zdirection respectively.

For px=-2.6×1029kgm/s, py=-1.0×1029kgm/sand pz=0,

p=-2.6×1029kgm/s2+-1.0×1029kgm/s2+0=2.785×1029kgm/s

Write the expression for the unit vector p^.

p^=pp

Here, pis the momentum of the planet and pis the magnitude of the momentum.

For p=-2.6×1029,-1.0×1029,0kg.m/sandp=2.785×1029kg.m/s .

p^=-2.6×1029,-1.0×1029,0kg.m/s2.785×1029kg.m/s=-0.9335,-0.359,0

Rewrite equation (1)

F∥=F.p^p^

For p^=-0.9335,-0.359,0and F=-2.5×1022,-1.4×1023,0NF=-2.5×1022,-1.4×1023,0N×-0.9335,-0.359,0×-0.9335,-0.359,0=2.33375×1022+5.026×1022N×-0.9335,-0.359,0=7.3635×1022N×-0.9335,-0.359,0=-6.87×1022,-2.64×1022,0N

04

Determination of the perpendicular force of the planet

The equation of force for the planet can be expressed as,

Fnet=F∥+FF⊥=Fnet-F∥

For Fnet=-2.5×1022,-1.4×1023,0N, and F∥=-6.87×1022,-2.64×1022,0N.

F⊥=-2.5×1022,-1.4×1023,0N--6.87×1022,-2.64×1022,0N=4.37×1022,-1.13×1023,0N

Thus, the values of F∥and F⊥are -6.87×1022,-2.64×1022,0Nand 4.37×1022,-1.13×1023,0N respectively.

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