What constant horizontal force is required to drag a 5 kg block along a horizontal surface with an acceleration of 1 ms-2 if the coefficient of
sliding friction between the block and the surface is 0.5.

25N

Explanation:

formula=> Frictional force= coefficient of friction x normal reaction

normal reaction is mass x gravity(10N/kg)

so Frictional force= 0.5x5x10

=25N

but that is the Frictional force not the constant force

to get the constant force, subtract the Frictional force from the weight of the block

weight= mass x gravity

= 5x10

= 50N

50N-25N

=25N

the chart show the masses and velocities of two colliding objects that stick together after a collision.

according to the law of conservation of momentum, the momentum of the object after the collision is  

answer

1,500

kg • m/s.

that tool is called an altimeter which measures your altitude which can be used to tell which atmosphere you are currently in, including the stratosphere.

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