1. Munhu ari muelevator inokwira kumusoro nespeed isingachinji . Huremu hwemunhu wacho i800 N. Tambo yeelevator inobva yatyoka, saka elevator inodonha. Tsvaga simba rakajairika rinoitwa nepasi peelevator kumunhu nguva pfupi tambo yeelevator isati yatyoka uye mushure mekunge yatyoka.
A. 800 N uye 0
B. 800 N uye 800 N
C. 1600 N uye 0
D. 1600 N uye 800 N
Zvinozivikanwa:
Kurema (w) = 800 Newton
Zvinodiwa: Simba rakajairika (N)
Solution:
Tambo yerifiti isati yadambuka
Kana munhu akamira pasi pechikwidzi, huremu hunoshanda pamunhu apo divi remunhu riri pasi. Munhu iyeye anenge akadzikama zvekuti panofanira kunge paine simba rakajairika rinoshanda pamunhu, apo divi resimba rakajairika riri kumusoro uye hukuru hwesimba rakajairika hwakafanana nehukuru hwehuremu.
Nekuti munhu wacho anenge akadzikama muelevator uye elevator inofamba nekumhanya kwakasimba (hapana kukurumidza), saka hapana simba rekuita chimwe chinhu pamunhu wacho.
∑F = 0
N – w = 0
N = w
N = 800 Newton
Mushure mekunge tambo yerifiti yadambuka
Kana tambo yerifiti yadambuka, rifiti nemunhu zvinowira pamwe chete, uko hukuru negwara rekumhanya kwadzo zvakafanana nekumhanya nekuda kwesimba rinokwevera pasi. Hapana simba rakajairika pamunhu.
Mhinduro chaiyo ndeinoti A.
2. Bhokisi rine huremu hwemagiramu makumi maviri rinofamba nekumhanya kusingachinji pasi rakatwasuka nekumhanya kusingachinji kana paine simba rekunze re2 N rinoshanda pabhokisi. Sarudza hukuru hwesimba rekukweshana rinoonekwa nebhokisi.
A. 0.3 N
B. 1.4 N
C. 2.0 N
D. 3.6 N
Zvinozivikanwa:
Huremu (m) = magiramu makumi maviri
Simba (F) = 2 Newton
Zvinodiwa: Hukuru hwesimba rekukweshana rinoonekwa nebhokisi.
Solution:
Zvichibva pamutemo wekutanga waNewton wekufamba, kana bhuroko richifamba nekumhanya kusingachinji, bhuroko harina kumhanyisa. Bhuroko rinofamba nekumhanya kusingachinji, uye hapana kumhanyisa kana:
– Hukuru hwesimba rekukweshana (F fric ) hwakafanana nehukuru hwesimba rekunze (F)
– Simba rekukweshana (F fric ) rine divi rakapesana nerekunze (F)
Shandisa mutemo wekutanga waNewton wekufamba:
∑ F = 0
F – F fric = 0
F = F fric
F fric = 2 Newton
Mhinduro chaiyo ndeinoti C.
3. Nzvimbo yakatsetseka yakatsetseka ine urefu hwe 0.6 m uye kukwirira kwe 0.4 m. Bhokisi rine huremu hwe, 1350 N richakwira kumusoro uchishandisa nzvimbo yakatsetseka. Sarudza hukuru hwesimba rinodiwa kuti bhokisi rifambiswe.
A. 100 N
B. 300 N
C. 600 N
D. 900 N
Zvinozivikanwa:
Kurema kwebhuroko (w) = 1350 Newtons
hyp = 0.6 m
vakapesana = 0.4 m
Zvinodiwa: Simba shoma
Solution:
hyp = ac = 0.6 m
opp = bc = 0.4 m
Chivi θ = bc / ac = 0.4 / 0.6 = 4/6 = 2/3
Zvichibva pamutemo wekutanga waNewton wekufamba, bhokisi rinotanga kufamba richikwira kumusoro ipapo simba rekunze (F) rinofanana nechikamu chakatarwa chehuremu (w x ).
∑ F = 0
F – w x = 0
F = w x
Kana F = w x , chinhu chinotanga kufamba chichienda kumusoro nekufamba kwemhepo nguva dzose.
w x = w chivi θ = (1350)(2/3) = (2)(450) = 900 Newtons
Mhinduro chaiyo ndiD.
4. Masimba matatu, F 1 = 22 N, F 2 = 18 N uye F 3 = 40 N anoita pabhuroko. Mufananidzo upi unotsanangura mutemo wekutanga waNewton.
Solution:
Mutemo wekutanga waNewton: Simba remagetsi (ΣF) = 0.
A. F 1 + F 2 – F 3 = 22 N + 18 N – 40 N = 40 N – 40 N = 0
B. F 2 + F 3 – F 1 = 18 N + 40 N – 22 N = 58 N – 22 N = 36 N (kurudyi)
C. F 2 + F 3 – F 1 = 18 N + 40 N – 22 N = 58 N – 22 N = 36 N (kurudyi)
D. F 1 + F 3 – F 2 = 22 N + 40 N – 18 N = 62 N – 18 N = 44 N (kuruboshwe)
