Ek = 1/2 mv^2
9 × 10^4 = 1/2 × 800 × v^2
9 × 10^4/400 = 400 v^2 / 400
9 × 10^4/400 = v^2
√225 = v
15 ms⁻¹ = v
That's the only way I know how to work it out
I think in this case velocity and speed would be considered the same because me
s = d/t and v=d/t
one is distance travelled and the other is displacement of a body
Answer:
<em>The velocity after 12s is 50.4m/s</em>.
Explanation:
<em>In acceleration formula make velocity the </em><em>subject.</em>
<em> acceleration(a) = velocity(</em>v)÷time(t)
<h3><em> </em><em>velocity</em><em> </em><em>(</em><em>v)</em><em> </em><em>=</em><em> </em><em>acceleration</em><em>(</em><em>a)</em><em>×</em><em>t</em><em>ime</em><em>(</em><em>t)</em></h3>
<em>V </em><em>=</em><em> </em><em>4</em><em>.</em><em>2</em><em>m</em><em>/</em><em>s²</em><em>×</em><em>1</em><em>2</em><em>s</em>
<em>V </em><em>=</em><em> </em><em>5</em><em>0</em><em>.</em><em>4</em><em>m</em><em>/</em><em>s</em>
<em>Therefore</em><em> the</em><em> </em><em>velocity</em><em> </em><em>after</em><em> </em><em>1</em><em>2</em><em>s</em><em> </em><em>is </em><em>5</em><em>0</em><em>.</em><em>4</em><em>m</em><em>/</em><em>s.</em>
Linear momentum has to be conserved. It was zero before the thread eas burned ... when nothing was moving ... so the momentum of the masses moving in opposite directions has to add up to zero. ... Momentum = mass times speed. ... In one direction, you have 5 kg times 1/5 m/s= 1 kg-m/s. ... We need 1 kg-m/s in the other direction. ... 7 kg times speed = 1 kg-m/s. ... Can you finish it from here ?
Answer: 3.75 joules
Explanation:
Given that:
Mass of acorn = 0.300 kilograms
velocity = 5.oo m/s
Kinetic energy = ?
Since, kinetic energy is the energy possessed by a moving object, its value depends on the mass M and velocity V of the acorn.
Thus, Kinetic energy = 1/2 x mv^2
= 1/2 x 0.300kg x (5.00m/s)^2
= 0.5 x 0.3kg x (5.00m/s)^2
= 0.15 x (5.00m/s)^2
= 3.75 joules
Thus, the kinetic energy of the falling acorn is 3.75 joules
Kinetic energy = 1/2mv^2
=1/2(25)(1^2)
= 12.5J
