The speed of the car is 75 km/h
These are the formulas that we have to remember before solving the problem.
Speed is the rate of change of distance.
v = speed ( m/s )
d = distance ( m )
t = time ( s )
Acceleration is the rate of change of velocity.
a = acceleration ( m/s² )
Δv = change in speed ( m/s )
t = time ( s )
Let us now tackle the problem!
Given:
distance = d = 150 km
time taken = t = 7200 s = 2 hours
Unknown:
velocity = v = ?
Solution:
The acceleration of the car is 0 m/s² because it travels with constant speed.
We could also plot the distance vs time graph as shown in the attachment.
Grade: Middle School
Subject: Physics
Chapter: Kinematics
Keywords: indycar top speed of a fastest police car has ever gone
The car's speed is 75 km/hour, as determined by dividing the total distance travelled (150 km) by the total time taken (2 hours).
To answer this question, we use the
formula for speed
, which is distance traveled divided by the time taken. Here, the distance travelled by the car is 150 km and the time taken is 7200 s (which is equal to 2 hours). Therefore, the speed will be 150 km divided by 2 hours, resulting in a speed of
75 km/hour
, stated to the correct number of significant figures.
#SPJ6
Answer:
I will move way from my friend.
Explanation:
As I shoot the paintball towards my friend, the gun exerts a force on it that sends it moving towards my friend, and according to newtons third law, the paintball exerts an equal and opposite force on me, which causes me to move in the opposite direction of the movement of the paintball; this direction is away from my friend.
Answer: The entangled players would move with a speed of 0.2 m/s in the direction direction of the motion of second soccer player.
Explanation:
From law of conservation of momentum,
Initial momentum of the closed system = final momentum of the closed system
Since, no external force is acting on the players, total momentum would be conserved.
m₁u₁+m₂u₂=(m₁+m₂)v
where, m₁ is the mass of one soccer player = 40 kg
u₁ is its initial velocity before collision = 4 m/s
m₂ is the mass of the other soccer player = 60 kg
u₂ is the initial velocity before collision = - 3 m/s (∵opposite direction)
After collision, the two players get entangled and hence move with the same final velocity v.
40 kg × 4 m/s - 60 kg × 3 m/s = (40 kg + 60 kg ) v
160 kg m/s - 180 kg m/s = 100 kg v
v = -0.2 m/s
Hence, the entangled players would move with a speed of 0.2 m/s in the direction direction of the motion of second soccer player.