问题
选择题
在盛着水的玻璃杯中放入一质量是1kg的松木块，木块静止在水面上时受到的浮力是（ ）
A．1kg
B．10N
C．大于10牛
D．小于10牛
答案
因松木块漂浮在水面上，所以物体受到的浮力等于物体重力；
即浮力F=G=mg=1kg×10N/kg=10N；
故选B．
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在盛着水的玻璃杯中放入一质量是1kg的松木块，木块静止在水面上时受到的浮力是（ ）
A．1kg
B．10N
C．大于10牛
D．小于10牛
因松木块漂浮在水面上，所以物体受到的浮力等于物体重力；
即浮力F=G=mg=1kg×10N/kg=10N；
故选B．
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