Because of your expert physics skills, you have been hired as an analyst in a court case involving an automobile accident. The accident involved a 2,402 kg car (car A) which approached a stationary car of mass 1,506 kg (car B). The driver of car A slammed on his brakes(locking his wheels) 18 m before he/she crashed into car B. After the collision, car A slid 19 m forward while car B slid 22 m forward (Note: the cars did not stick together upon colliding). The coefficient of kinetic friction between the locked wheels and the road was measured to be 0.78. Calculate the speed of car A, in mph, at the moment he began braking. (1 mph = 0.447 m/s) fyi: The speed limit was 55 mph.

Explanation:

We shall calculate the negative work done by friction on both the cars which exhausted the kinetic energy of car A

work done by friction on car A

μ mg x d

μ is coefficient of friction  mg is weight of the car and   d is distance of slippage

= .78x 2402 x 9.8 x (18 +19)

= 679352.85 J

Work done by friction on car B

μ is coefficient of friction  mg is weight of the car and   d is distance of slippage

= .78x 1506  x 9.8 x 22

= 253261 J

Total = 932613.85 J

Now if v be the velocity of car A

1/2 m v ² = 932613.85

v² = (932613.85 x2) / 2402

= 776.53

v = 27.87 m /s

= 27.87 / .447

= 62.34 mph

the word that best describes martin luther king jr.'s tone in the video is dignified

martin luther king, jr. was a social activist and baptist minister who played a key role in the american civil rights movement from the mid-1950s until his assassination in 1968. the video shows his manner and attitude having or showing a composed or serious manner that is worthy of respect so dignified is the correct answer

gpe = mass x gravity constant x height or… gpe = mgh

where… mass: measured in kilograms (kg)

gravity: gravity constant on earth = 10.00 m/s2

height: measured in meters (m)

gpe: measured in joules (j) or kilojoules (kj)

how do you solve gpe?

gravitational potential energy (gpe) is the energy an object has because of its position above the. ground.

gpe = mass x gravity constant x height or… gpe = mgh.

mass:

note: to earn full marks when solving science word problems, you must show your work:

formula.

example:

given values:

mass = 0.3 kg.