The driver in a motor car, of which the total mass is 800kg and which is traveling at 20ms-1, suddenly observes a stationary dog in his path 50m ahead. If the car brakes can exert a force of 2000N, what will most likely happen?

brainiac140

5 years ago

F=ma
2000=800×a
a=2000÷800
a=2.5
a=2.5
V^2=u^2+2as
400=2×2.5×s
S=400÷5
S=80
80-50=30
The car will stop 30m after hitting the dog

alvan1

1 year ago

1. Mass of the car (m) = 800 kg


2. Initial velocity of the car (u) = 20 m/s


3. Force exerted by the brakes (F) = 2000 N


4. Distance to the dog = 50 m



The deceleration caused by the brakes can be calculated using Newton's second law: f = ma

a = F/m = 2000/800= 2.5m/s^2
(deceleration is negative because it's acting opposite to the motion).
Now, we can find the stopping distance s, using the 4th equation of motion:

v^2 = u^2 + 2as
V = 0, u = 20m/s, a =-2.5m/s² (deceleration is negative because it's acting opposite to the motion).

Rearranging the equation to solve for :

0 = (20)^2 + 2(-2.5)d

0 = 400 - 5d

5d = 400

d = 400/5= 80m

Since the car needs 80 m to stop and the dog is only 50 m away, the car will not be able to stop in time. The car will stop 30 m after hitting the dog.

So, the correct answer is: B. the car will stop 30m after hitting the dog.

JazrealMEMEs

3 years ago

I got it Sha but 🙄
There was no indication of a correct answer
My school please rectify this error Option B should be correct ✔️

Kellygee01

3 years ago

Option B is suppose to be "the car will stop 30m after hitting the dog" and that's the correct answer

Doclord

3 years ago

The driver must be reckless 😂😂😂😂😂

Akeemtobby

3 months ago

pepl ooooo

Ibraahiim

1 year ago

anyways just a joke 🤣
find the and the accelerated using the values given and then use the formula v² = u² + 2as

Anthony_Akaniyene

2 years ago

Option is correct for the question but no option was picked and I was marked down for the question despite getting the correct answer

Ibraahiim

1 year ago

🙄🙄 the dog would run away as it isn't a moron like you jamb

Irresistible

5 years ago

The driver in a motor car, of which the total mass is 800kg and which is traveling at 20ms-1, suddenly observes a stationary dog in his path 50m ahead. If the car brakes can exert a force of 2000N, what will most likely happen?
A. the car will be able to stop immediately the driver notices the dog
B. the car will stop 3pm after hitting the dog
C. the car will stop 20m in front of the dog
D. the driver will quickly reverse the car
E. the car will stop 5m beyound the dog