0
-- You haven't said what the object's speed was at the beginning of the
25 minutes. We'll assume that it started from rest at the beginning of
this whole exercise.
-- We're also going to work exclusively with the object's speed. Since you
haven't said anything about the direction in which it moves at any moment,
we have no way to work with velocity. Fortunately, it doesn't matter.
The motion occurs in three distinct periods, which we'll consider separately:
Period I:
Zero to 90 m/s in 25 minutes.
Average speed = 45 m/s.
Distance = (average speed) x (time) = (45 meter/sec) x (60 sec/min) x (25 min) = 67,500 meters.
Period II:
(90 meters/sec) x (3,600 sec/hour) x (2 hours) = 648,000 meters
Period III:
A perfect time-reversal of Period-I ... like running the video backwards.
Same distance as Period-I = 67,500 meters.
Total distance = (67,500) + (648,000) + (67,500) = 783 kilometers.
======================================================
Period-I
S = vit + 1/2 a t2
vi = 0
Acceleration = [ (90 meter/sec) x (1/25 min) ] x (1 min/60 sec) = 0.06 meter/sec2
t = 25 minutes = 1,500 sec
1/2 a t2 = 1/2 (0.06) (1,500)2 = 67,500 m
Period-II
S = v t = (90 meters/sec) x (2 hours) x (3,600 sec/hour) = 648,000 m
Period-III
Either recognize that Period-III is exactly the same as Period-I in reverse,
or else
you can use
S = vit + 1/2 a t2
vi = 90 meters/sec
t = 25 min = 1,500 sec
Acceleration = -0.06 meter/sec2
vit + 1/2 a t2 = (90)(1,500) + 1/2(-0.06)(1,500)2 = (135,000) + (-67,500) = 67,500 m
What else can I help you with?
Stopping a vehicle with good brakes from 20 miles per hour under good conditions required about?
Stopping a vehicle with good brakes from 20 miles per hour under good conditions typically requires a distance of about 20 to 30 feet. This distance can vary based on factors such as the type of brakes, tire condition, and road surface. Generally, the stopping distance includes the reaction time of the driver and the braking distance itself.
If only external force can change the velocity of a body how can the internal force of the brakes bring a car to rest?
It is not the force of the brakes that is stopping the car but rather external force of friction between tires and the road. Notice that no matter what the force at the brakes is, the car won't stop if there is no friction there(ie. the road is slippery). This is an excellent question. Consider the NASA space shuttle. It has brakes, yet the brakes work only on the ground - only while the shuttle is landing. Why? In space, the brakes have nothing to react against. So, as the questioner suspects, the internal forces of the brakes alone are not sufficient to change the velocity of the space shuttle. But once the shuttle lands, and is rolling down the runway, applying the brakes creates friction between the wheels and the runway. And it is the external force of the runway pushing back against the braking wheels that causes the shuttle to slow down.
What is the best way to stop with ABS brakes on ice and snow?
To stop with ABS brakes on ice and snow, apply steady pressure to the brake pedal. Do not pump the brakes, as ABS brakes are designed to prevent wheel lock-up. Maintain a safe following distance and make smooth steering inputs to help maintain control while braking.
This is the distance your vehicle travels from the moment you first see a hazard to the moment you come to a full stop?
That distance is known as the total stopping distance, which consists of both the thinking distance (distance traveled while recognizing a hazard and reacting) and the braking distance (distance traveled from applying the brakes to coming to a complete stop). The total stopping distance can vary depending on factors such as speed, road conditions, and vehicle condition.
A 735 kg car moving at 20 ms brakes to a stop The brakes contain about 15 kg of iron which absorbs the energy What is the increase in temperature of the brakes?
To find the increase in temperature of the brakes, you need to calculate the total kinetic energy of the car before braking and then determine the amount of energy absorbed by the brakes during braking. Using the equation for kinetic energy (0.5 x mass x velocity^2) for the car before braking and equating it to the energy absorbed by the brakes, you can then find the increase in the temperature of the brakes using the specific heat capacity of iron.
What the total distance of a body acquires the velocity of 90 km per hour in 25 minutes it then continuous for 2 hours when brakes applied it comes into rest in 25 minutes?
255 km
Why are larger brakes prefered over smaller brakes in vehicles?
Larger brakes = shorter stopping distance.
Can hot brakes cause a tire fire?
If brakes are sticking and you drive for a long distance, then yes
What is braking distance composed of?
Braking distance is usually measured by how fast you can stop at 60mph, 60-0, the make of a car is the factor of the stopping distance, each car varies. Your car can have disc brakes or drum brakes or both. Disc brakes are more effective than drum brakes. But braking distance is usually showed by how many feet it takes to stop from 60mph
If you find skid marks 180 meters long and assuming the deceleration was 10 minutes how fast was the car traveling before it hit the brakes?
To determine the initial speed of the car before it hit the brakes, we can use the formula for deceleration: ( v^2 = u^2 + 2as ), where ( v ) is the final velocity (0 m/s when the car stops), ( u ) is the initial velocity, ( a ) is the deceleration, and ( s ) is the distance (180 meters). Assuming a deceleration of 10 m/s² (not minutes), rearranging the formula gives ( u = \sqrt{v^2 - 2as} ). Plugging in the values, we find ( u = \sqrt{0 - 2(-10)(180)} = \sqrt{3600} = 60 ) m/s, which is approximately 216 km/h.
What is braking distance?
The distance a vehicle will travel between putting on the brakes and coming to a stop.
What is an element of total stopping distance?
An element of total stopping distance is perception distance, which is the distance a vehicle travels from the moment a driver detects a hazard to when they start applying the brakes. Other elements include reaction distance (distance traveled while the driver reacts) and braking distance (distance traveled after applying the brakes).
How do you decrease velocity of a moving car?
You increase the frictional force by applying the brakes.
Can a moving body have velocity and acceleration in opposite directions explain with in example?
Of course. A car with brakes applied and slowing down has forward velocity and rearward acceleration.
After a short distance 1990 Jaguar XJS brakes slowly apply until the wheels are solidly locked The brake pedal is solid After 30 minutes they are fully released again What is the problem?
overheating
What should you do if your brakes become wet?
While driving, apply the brakes gently for a short distance, as you maintain your speed.
Do drum brakes work better than disk brakes?
No, they are inferior to disc brakes. Drum brakes were used from the beginning of the auto up until the late 60s. Drum brakes are more prone to overheating than disc brakes. Disc brakes also shed water much better than drum brakes which improves stopping distance in wet conditions. Disc brakes apply pressure more evenly than drum brakes thus improving stopping distance. Disc brakes are superior in every way.
