Mochini o 6 o bonolo (Lever e sekametseng) - Mathata le Litharollo
1.
Ke sefofane sefe se sekametseng se nang le melemo e tšoanang ea mechini
A. (1) le (2)
B. (1) le (3)
C. (2) le (3)
D. (2) le (4)
tharollo
Sefofane se sekametseng ke e 'ngoe ea mechini e bonolo. Mechine e bonolo ke lisebelisoa tse thusang batho ho etsa mosebetsi. Sefofane se sekametseng se sebelisetsoa ho nolofalletsa batho ho phahamisa ntho ho fihlela bophahamong bo itseng.
Molemo oa mechine oa sefofane se sekametseng ke papiso ea bolelele ba ho sekamela le bophahamo ba ho sekamela.
Molemo oa mechine oa sefofane se sekametseng 1 = 50 cm / 30 cm = 5/3
Molemo oa mechine oa sefofane se sekametseng 2 = 5 cm / 4 cm = 5/4
Molemo oa mechine oa sefofane se sekametseng 3 = 50 cm / 40 cm = 5/4
Molemo oa mechine oa sefofane se sekametseng 4 = 5 cm / 3 cm = 5/3
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2.
Sebaka AB = BC = CD = DE, fumana matla a ho kenya a lokelang ho fanoa ntlheng ea E e le hore ho be le lever e leka-lekaneng.
Tse tsejoang:
AB = BC = CD = DE = l
Sebaka se pakeng tsa matla a tlhahiso le fulcrum ( a ) = l
Sebaka se pakeng tsa matla a ho kenya le fulcrum ( b ) = 3l
Matla a tlhahiso (w) = 900 Newton
Ho batloa : Matla (F)
Tharollo:
Molemo oa mechini:
MA = b / a = 3l/l = 3
Boholo ba matla:
MA = w / F
F = w / MA
F = 900 Newtons / 3
F = 300 Newton
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3.
E le hore lever e leka-lekane, joale fumana boholo ba matla a eona a ho kenya.
tharollo
Fumana sebaka se pakeng tsa matla a ho kenya le fulcrum ( b )
Tse tsejoang:
Sebaka se pakeng tsa matla a tlhahiso le fulcrum ( a ) = 25 cm
Matla a tlhahiso (w) = 480 Newton
Matla a ho kenya (F) = 160 N
Ho batloa: Sebaka se pakeng tsa matla a ho kenya le fulcrum (b)
Tharollo:
Molemo oa mechini:
MA = w / F = 480 N / 160 N = 3
Sebaka se pakeng tsa matla a ho kenya le fulcrum (b)
MA = b / a
3 = b / 25 cm
b = (3)(25 cm)
b = 75 cm
Fumana boholo ba matla (F)
Tse tsejoang:
Sebaka se pakeng tsa matla a tlhahiso le fulcrum ( a ) = 25 cm – 10 cm = 15 cm
Boima ba ntho (w) = 480 Newtons
Sebaka se pakeng tsa matla a ho kenya le fulcrum ( b ) = 75 cm
Ho batloa: Matla a ho kenya (F)
Tharollo:
Melemo ea mechini:
MA = b / a
MA = 75 cm / 15 cm
MA = 5
Boholo ba matla (F):
MA = w / F
F = w / MA
F = 480 Newtons / 5
F = 96 Newton
E le hore lever e be boemong bo leka-lekaneng, matla a ho kenya a fokotsoa ka 64 Newton (160 N - 96 N).
4. Karolelano ea bolelele ba a le b setšoantšong se ka tlase ke a: b = 1: 2.2. Boleng bo tlase ba matla a F ho phahamisa ntho B ka boima ba 330 Newtons ke…. Newton
A. 100
B. 150
C. 2200
D. 7260
Tse tsejoang:
Sebaka se pakeng tsa matla a tlhahiso le fulcrum ( a ) = 1
Sebaka se pakeng tsa matla a ho kenya le fulcrum (b) = 2.2
Boima (w) = 330 Newton
Ho batloa: Matla a ho kenya (F)
Tharollo:
Melemo ea mechine ea lever:
MA = w / F = b / a
MA = monyetla oa mechini , w = boima, F = matla a ho kenya, b = sebaka se pakeng tsa matla a ho kenya le fulcrum, a = sebaka se pakeng tsa matla a ho hlahisa le fulcrum
w / F = b / a
330 / F = 2.2 / 1
330 / F = 2.2
330 / 2.2 = F
F = 150 Newton
Karabo e nepahetseng ke B.
5. Seithuti se sutumelletsa ntho ka matla a F ho tloha ntlheng ea A ho ea ntlheng ea B, joalo ka ha ho bontšitsoe setšoantšong se ka tlase. Haeba khohlano pakeng tsa ntho le kolobe e hlokomolohuoa, fumana molemo oa mechini.
A. 4
B. 5/3
C. 5/4
D. ¾
Tse tsejoang:
Bophahamo ba sefofane se sekametseng (y) = limithara tse 4 - limithara tse 1 = limithara tse 3
Bolelele ba sefofane se rapameng (x) = limithara tse 4
Ho batloa: Molemo oa mechini (MA)
Tharollo:
Bala bolelele ba sefofane se sekametseng o sebedisa equation ya Pythagoras :
R = √3 2 +4 2 = √9+16 = √25 = limithara tse 5
Melemo ea mechine ea sefofane se sekametseng:
KM = R / y
KM = limithara tse 5 / limithara tse 3
KM = 5/3
Karabo e nepahetseng ke B.
6. Molemo oa mechini oa lever o ka eketsoa ka…
A. Khutsufatsa tsela ea tšekamelo
B. holisa sekhutlo sa tšekamelo
C. fokotsa sekhutlo sa tšekamelo
D. e fokotsa matla a sebelisoang ho tsamaisa lintho
Tharollo:
Tekanyo ea melemo ea mechini ea sefofane se sekametseng:
Molemo oa mechine = bolelele ba sefofane se sekametseng/bophahamo ba sefofane se sekametseng
– Molemo oa mechini o lekana ka ho toba le bolelele ba sefofane se sekametseng 'me ka hona molemo oa mechini oa eketseha haeba bolelele ba sefofane se sekametseng bo eketseha.
– Molemo oa mechini o lekana ka tsela e fapaneng le bophahamo ba sefofane se sekametseng, ka hona, molemo oa mechini oa fokotseha haeba bophahamo ba sefofane se sekametseng bo eketseha 'me molemo oa mechini oa eketseha haeba bophahamo ba sefofane se sekametseng bo fokotsehile.
- Haeba sekhutlo se fokotswa, bophahamo ba sefofane se sekametseng bo a fokotseha. Molemo wa mechini o a eketseha haeba bophahamo ba sefofane se sekametseng bo fokotswa. Kahoo haeba sekhutlo se fokotswa, monyetla wa mechini o a hola.
Haeba sekhutlo se hodisitswe, bophahamo ba sefofane se sekametseng bo a eketseha. Molemo wa mechini o a fokotswa haeba bophahamo ba sefofane se sekametseng bo eketswa. Kahoo haeba sekhutlo se hodisitswe, monyetla wa mechini o a fokotswa.
Karabo e nepahetseng ke C.
