Similarity between velocity and momentum

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Momentum, defined as the product of mass and velocity, is a vector quantity, while mass is a scalar. Both momentum and velocity share similarities, such as being collinear vectors that have the same unit vector. The magnitude of momentum increases when mass is greater than one, but this is dependent on the choice of units, making comparisons arbitrary. Additionally, force represents the change in momentum when mass is constant, linking acceleration and momentum through their definitions. Overall, the discussion highlights the complexities and arbitrary nature of comparing magnitudes of momentum and velocity.
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as momentum is product of mass and velocity ,it is a vector quantity but mass is a scalar.when a scalar is multiplied to a vector ,it's magnitude increases .then there must certain similarities between velocity and momentum.
 
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The similarity is that the vectors are collinear, i.e. they share the same unit vector. Also, the magnitude only increases if the scalar (mass) is greater than 1.
Also, since acceleration is the change in velocity, force is the change in momentum if you assume mass to be constant.
##A = \frac{d}{dt}V##
##F=mA = m\frac{d}{dt}V=\frac{d}{dt}(mV) ##
 
RUber said:
The similarity is that the vectors are collinear, i.e. they share the same unit vector. Also, the magnitude only increases if the scalar (mass) is greater than 1.
Since mass is not a unitless quantity, whether it is greater or less than one depends on one's choice of units. It is arbitrary. Since momentum and velocity are not unitless quantities, whether one has larger magnitude than the other also depends on one's choice of units. It is also arbitrary.

The comparison of magnitudes seems pointless. It is like asking whether an apple is rounder than an orange is tall.
 
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