Assuming the driver starts slamming the brakes immediately, the car moves by uniformly decelerated motion, so we can use the following relationship
(1)
where
a is the deleceration
S is the distance covered after a time t
is the velocity at time t
is the initial speed of the car
The accident is 80 m ahead of the car, so the minimum deceleration required to avoid the accident is the value of a such that S=80 m and
(the car should stop exactly at S=80 m to avoid the accident). Using these data, we can solve the equation (1) to find a:
And the negative sign means it is a deceleration.
Answer:
12.24 m/s
Explanation:
Speed: This can be defined as the rate of change of distance with time. The S.I unit of speed is m/s.
Using the formula,
a = v/t................ Equation 1
Where a = acceleration of the sprinter, v = speed of the sprinter, t = time.
making v the subject of the equation,
v = at ................. Equation 2
Given: a = 5.1 m/s², t = 2.4 s.
Substitute into equation 2
v = 5.1(2.4)
v = 12.24 m/s.
Hence, the speed of the sprinter = 12.24 m/s
Complete Question
An infinite sheet carries a uniform, positive charge per unit area. The electric field produced by the sheet is represented by parallel lines drawn with a density N lines per m2 that are perpendicular to and away from the sheet. The charge per unit area on the sheet is doubled. How should the density of the electric field lines be changed?
A It should stay the same
B It should be quadrupled.
C It should be quintupled
D It should be doubled.
E It should be tripled
Answer:
Option D is the correct option
Explanation:
Generally electric field is mathematically represented as
Where 
is the charge per unit area (Charge density )
From the question we are told that is doubled hence the
Looking the equation above we see that the value of the electric field will also double given that it is directly proportional to the charge density
The outlaw that was <span>executed by hanging "in the spring of '25" is identified as the HIGHWAYMAN.
This is one of the characters in the song, "American Remains", sang by The Highwaymen. The group consisted of </span><span>Johnny Cash, Waylon Jennings, Willie Nelson and Kris Kristofferson. Other characters in the song were a sailor, a dam builder, and a pilot of a starship.
</span>
This is the first stanza of the song:
"I was a highwayman. Along the coach roads I did ride
<span>With sword and pistol by my side </span>
<span>Many a young maid lost her baubles to my trade </span>
<span>Many a soldier shed his lifeblood on my blade </span>
<span>The b*stards hung me in the spring of twenty-five </span>
<span>But I am still alive."</span>
