Answer:
= -32.53 m / s
this velocity is directed downwards
Explanation:
This is a free fall exercise, let's use the expression
= v_{oy}^{2} + 2 g (y -yo)
where we are assuming that there is friction with the air, as the body falls its initial velocity is zero
v_{oy} = √ 2g (y - y₀)
let's calculate
v_{y} = √ (2 9.8 (0-54.0))
= -32.53 m / s
this velocity is directed downwards
Complete Question
Q. Two go-carts, A and B, race each other around a 1.0km track. Go-cart A travels at a constant speed of 20m/s. Go-cart B accelerates uniformly from rest at a rate of 0.333m/s^2. Which go-cart wins the race and by how much time?
Answer:
Go-cart A is faster
Explanation:
From the question we are told that
The length of the track is
The speed of A is
The uniform acceleration of B is
Generally the time taken by go-cart A is mathematically represented as
=>
=>
Generally from kinematic equation we can evaluate the time taken by go-cart B as
given that go-cart B starts from rest u = 0 m/s
So
=>
=>
Comparing we see that
is smaller so go-cart A is faster
Answer:
90,000 J
Explanation:
Kinetic energy can be found using the following formula.
where <em>m </em>is the mass in kilograms and <em>v</em> is the velocity in m/s.
We know the object has a mass of 50 kilograms. We also know it is a traveling at a rate of 60 m/s. Velocity is the speed of something, so the velocity of the object is 60 m/s.
<em>m</em>=50
<em>v</em>=60
Substitute these values into the formula.
First, evaluate the exponent: 60^2. 60^2 is the same as multiplying 60, 2 times.
60^2=60*60=3,600
Multiply 50 and 3,600
Multiply 1/2 and 3,600, or divide 3,600 by 2.
Add appropriate units. Kinetic energy uses Joules, or J.
The kinetic energy of the object is 90,000 Joules