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Q. |
## In block brake, the normal reaction and frictional force act at the mid-point of the block. This is true only if the angle of contact is ____ |

A. | less than 45 degree |

B. | less than 60 degree |

C. | greater than 45 degree |

D. | greater than 60 degree |

Answer» A. less than 45 degree |

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