Question

An object has a velocity of 8 m/s and a kinetic energy of 480 J. What is the mass of the object? Formula=1/2mv^2 a(7.5 b(15 kg c(60 kg d(120 kg
nevermind i found the answer its (15 kg) because to solve for m its m= K2/v squared

Answer 1

Hello!

An object has a velocity of 8 m/s and a kinetic energy of 480 J. What is the mass of the object ?

We have the following data: 

KE (Kinetic Energy) = 480 J

m (mass) = ? (in Kg)

v (speed) = 8 m/s

Formula to calculate kinetic energy:

$\boxed{KE = \dfrac{1}{2}*m*v^2}$

Solving:

$KE = \dfrac{1}{2}*m*v^2$

$480 = \dfrac{1}{2}*m*8^2$

$480 = \dfrac{1}{2}*m*64$

$480*2 = 64*m$

$960 = 64\:m$

$64\:m = 960$

$m = \dfrac{960}{64}$

$\boxed{\boxed{m = 15\:Kg}}\end{array}}\qquad\checkmark$

Answer:  

b) 15 kg

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I Hope this helps, greetings ... Dexteright02! =)

Answer 2

The Kinetic Energy (K.E) of an object can be calculated as:

$K.E= \frac{1}{2}mv^{2}$

We are given:
K.E = 480 K
Velocity of the object = v = 8 m/s

Using the values, we get:

$480= \frac{1}{2}m(8)^{2} \\ \\ 480= \frac{1}{2}*64m \\ \\ 480=32m \\ \\ m=15$

Thus, the mass of the object will be 15 kg.

So the correct answer is option b