Question

Can anyone's send the answer of the 6 th ​

Answer 1

Answer:

As frictional force acts in opp direction it is given negative magnitude

Answer 2

$\huge\underline\blue{\sf Answer:}$

$\large\red{\boxed{\sf Force\:of\: friction=-4N }}$

$\huge\underline\blue{\sf Solution:}$

$\large\underline\pink{\sf Given: }$

• Mass of stone (m) = 1 kg

• Initial Velocity (u) = 20 m/s

• Final Velocity (v) = 0 m/

• Distance (s) = 50 m

$\large\underline\pink{\sf To\:Find: }$

• Force of friction between stone and ice (F) = ?

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From 3rd Equation of motion :-

$\large{\boxed{\sf v^2=u^2+2as }}$

$\large\implies{\sf 0^2=(20)^2+2×a×50}$

$\large\implies{\sf a=-4m/s^2 }$

negative sign (-) indicates that retardation takes place i.e Acceleration is acting against the motion of the stone .

Now ,

From Newton's 2nd law :-

$\large{\boxed{\sf Force=Mass×Acceleration}}$

$\large\implies{\sf F=1×-4 }$

$\large\implies{\sf F=-4N }$

$\large\red{\boxed{\sf Force\:of\: friction=-4N }}$

Hence ,

Force of friction between stone and ice is -4N