Ntxiv cov vectors siv cov khoom sib xyaw - teeb meem thiab kev daws teeb meem
1. Peb lub vectors raws li qhia hauv daim duab hauv qab no.
V1 = 30
V2 = 30
V3 = 40
Cov vectors uas tau los ntawm qhov no yog dab tsi.
Paub:
V 1 = 30, lub kaum sab xis ntawm V 1 thiab x axis = 30 o
V 2 = 30, lub kaum sab xis ntawm V 2 thiab x axis = 30 o
V 3 = 40, lub kaum sab xis ntawm V 3 thiab x axis = 0 o
Xav tau: Cov vectors tshwm sim
Tshuaj:
V 1x = (V 1 )(cos 30 o ) = (30)(0.5√3) = 15√3. Zoo vim tias cov vector no taw tes raws txoj kab x zoo (sab xis).
V 1y = (V 1 )(sin 30 o ) = (30)(0.5) = 15. Zoo vim tias cov vector no taw tes raws txoj kab y zoo (sab saud).
V 2x = (V 2 )(cos 30 o ) = (30)(0.5√3) = -15√3. Tsis zoo vim tias qhov vector no taw tes raws txoj kab x tsis zoo (sab laug).
V 2y = (V 2 )(sin 30 o ) = (30)(0.5) = 15. Zoo vim tias cov vector no taw tes raws txoj kab y zoo (sab saud).
V 3x = (V 3 )(cos 0 o ) = (40)(1) = 40. Zoo vim tias cov khoom vector no taw tes raws txoj kab x zoo (sab xis).
V 3y = (V 3 )(sin 0 o ) = (40)(0) = 0
Cov khoom ntawm cov vectors resultant:
V x = V 1x – V 2x + V 3x = 15√3 – 15√3 + 40 = 40
V y = V 1y + V 2y + V 3y = 15 + 15 = 30

2. Ob lub zog uas sib ncaj nraim rau ib leeg, F 1 = 12 N thiab F 2 = 5 N. Qhov tshwm sim ntawm ob lub zog yog dab tsi.
Paub:
Lub zog 1 (F1 ) = 12 Newton
Lub zog 2 (F2 ) = 5 Newton
Xav tau: Cov vectors tshwm sim ( ΣF)
Tshuaj:
ΣF 2 = F 1 2 + F 2 2 = 12 2 + 5 2 = 144 + 25 = 169
ΣF = √ 169 = 13 Newton
3. Peb lub vectors,
V1 = 30
V 2 = 30
V3 = 40
Txheeb xyuas cov vectors uas tau los.
Paub:
v 1 = 30, ua rau 30 o nyob ib ncig ntawm qhov tsis zoo ntawm x axis
v 2 = 30, ua rau 30 o nyob ib ncig ntawm lub x axis zoo
v 3 = 40, ua rau 0 o nyob ib ncig ntawm lub x axis zoo
Xav tau: Cov vectors tshwm sim
Tshuaj:
Cov khoom ntawm vectors:
v 1x = v 1 cos 30 o = (30)(0.5 √ 3) = -15 √ 3 ( Tsis zoo vim tias cov vector no taw tes raws txoj kab x tsis zoo (sab laug) )
v 1y = v 1 sin 30 o = (30)(0.5) = 15 ( Zoo vim tias cov vector no taw tes raws txoj kab y zoo (sab saud) )
v 2x = v 2 cos 30 o = (30)(0.5 √ 3) = 15 √ 3 ( Zoo vim tias cov khoom vector no taw tes raws txoj kab x zoo (sab xis ) )
v 2y = v 2 sin 30 o = (30)(0.5) = 15 ( Zoo vim tias cov vector no taw tes raws txoj kab y zoo (sab saud). )
v 3x = v 3 cos 0 o = (40)(1) = 40 ( Zoo vim tias cov khoom vector no taw tes raws txoj kab x zoo (sab xis). )
v 3y = v 3 sin 0 o = (40)(0) = 0
Cov khoom ntawm cov vectors resultant:
v x = – v 1x + v 2x + v 3x = -15 √ 3 + 15 √ 3 + 40 = 40
v y = v 1y + v 2y + v 3y = 15 + 15 = 30
Tus vector tshwm sim:

4. Qhov tshwm sim ntawm peb lub vectors raws li qhia hauv daim duab hauv qab no yog dab tsi :
Paub:
F1 = 3 Newtons, ua 60o txog qhov x axis zoo
F2 = 3 Newtons, ua rau 0 o nyob ib ncig ntawm qhov tsis zoo ntawm x axis
F3 = 6 Newtons , ua rau 60 o ncig lub y axis tsis zoo
Xav tau: Tus vector tshwm sim
Tshuaj:
Cov khoom ntawm vectors:
F 1x = F 1 cos 60 o = (3)(0.5) = 1.5 N ( Zoo vim tias cov khoom vector no taw tes raws txoj kab x zoo (sab xis ) )
F 1y = F 1 sin 60 o = (3)(0.5√3) = 1.5√3 N ( Zoo vim tias cov vector no taw tes raws txoj kab y zoo (sab saud) )
F 2x = F 2 cos 0 o = (3)(1) = -3 N ( Tsis zoo vim tias cov khoom vector no taw tes raws txoj kab x tsis zoo (sab laug) )
F 2y = F 2 sin 0 o = (3)(0) = 0
F 3x = F 3 cos 60 o = (6)(0.5) = 3 N ( Zoo vim tias cov khoom vector no taw tes raws txoj kab x zoo (sab xis ) )
F 3y = F 3 sin 60 o = (6)(0.5√3) = -3√3 N ( Tsis zoo vim tias cov vector no taw tes raws txoj kab y tsis zoo ( downward ) )
Cov khoom ntawm cov vectors resultant:
ΣF x = F 1x – F 2x + F 3x = 1.5 N – 3 N + 3 N = 1.5 N
ΣF y = F 1y + F 2y – F 3y = 1.5√3 N + 0 N – 3√3 N = -1.5√3 N
Tus vector tshwm sim:

5. Ob lub zog, F 1 = 15 N thiab F 2 = 9 N. Lub kaum sab xis ntawm ob lub vectors yog 60°. Qhov tshwm sim ntawm cov vectors yog dab tsi.
Xav tau:
Lub zog 1 (F 1 ) = 15 Newton
Lub zog 2 (F2 ) = 9 Newton
Lub kaum sab xis ( θ) = 60 o
Xav tau: Tus vector tshwm sim
Tshuaj:

6. Qhov tshwm sim ntawm peb lub vectors raws li qhia hauv daim duab hauv qab no yog dab tsi?
Paub:
F1 = 20 Newton, lub kaum sab xis ntawm F1 thiab x axis = 0
F 2 = 20 Newtons, lub kaum sab xis ntawm F 2 thiab x axis = 60
F 3 = 24 Newtons, lub kaum sab xis ntawm F 3 thiab x axis = 60
Xav tau: Tus vector tshwm sim
Tshuaj:
Cov khoom ntawm vectors:
F 1x = (F 1 )(cos 0) = (20)(1) = 20. Zoo vim tias cov khoom vector no taw tes raws txoj kab x zoo (sab xis )
F 1y = (F 1 )(sin 0) = (20)(0) = 0
F 2x = (F 2 )(cos 60) = (20)(0.5) = -10. Tsis zoo vim tias cov khoom vector no taw tes raws txoj kab x tsis zoo (sab laug)
F 2y = (F 2 )(sin 60) = (20)(0.5√3) = 10√3. Zoo vim tias cov vector no taw tes raws txoj kab y zoo (sab saud)
F 3x = (F 3 )(cos 60) = (24)(0.5) = -12. Tsis zoo vim tias cov khoom vector no taw tes raws txoj kab x tsis zoo (sab laug)
F 3y = (F 3 )(sin 60) = (24)(0.5√3) = -12√3. N tsis zoo vim tias cov vector no taw tes raws txoj kab y tsis zoo ( downward )
Cov khoom ntawm cov vectors resultant:
F x = F 1x – F 2x – F 3x = 20 – 10 – 12 = -2
F y = F 1y + F 2y – F 3y = 0 + 10√3 – 12√3 = -2√3
Tus vector tshwm sim:
