Answer:
i)-6.25m/s
ii)18 metres
iii)26.5 m/s or 95.4 km/hr
Explanation:
Firstly convert 90km/hr to m/s
90 × 1000/3600 = 25m/s
(i) Apply v^2 = u^2 + 2As...where v(0m/s) is the final speed and u(25m/s) is initial speed and also s is the distance moved through(50 metres)
0 = (25)^2 + 2A(50)
0 = 625 + 100A....then moved the other value to one
-625 = 100A
Hence A = -6.25m/s^2(where the negative just tells us that its deceleration)
(ii) Firstly convert 54km/hr to m/s
In which this is 54 × 1000/3600 = 15m/s
then apply the same formula as that in (i)
0 = (15)^2 + 2(-6.25)s
-225 = -12.5s
Hence the stopping distance = 18metres
(iii) Apply the same formula and always remember that the deceleration values is the same throughout this question
0 = u^2 + 2(-6.25)(56)
u^2 = 700
Hence the speed that the car was travelling at is the,square root of 700 = 26.5m/s
In km/hr....26.5 × 3600/1000 = 95.4 km/hr
Answer:
Explanation:
Let the potential difference between the plate is V . Then in the first case
Electric field E between plate
E₁ = V / d
where d is separation between plate
When the plate separation becomes d / 2
Electric field E between plate
E₂ = V / d /2
= 2 V / d =2E₁
Or twice the earlier field
D.What is the best angle to throw a ball for maximum distance? Because this is the only question in above all of them which has some scientific investigation like angle that is use in many of the physics relations.
The velocity of the ferry relative to the current is 4.5 m/s.
<h3>Relative velocity</h3>
- Relative velocity is the velocity of a body as observed from the reference point of another body either stationary or in motion.
Since the river is flowing parallel to the shore and the ferry is moving perpendicular to the shore, their velocities are at right angles to each other.
The two velocities form a right angled-triangle of sides 2, 4 and a hypotenuse which gives the relative velocity of the ferry to the current.
Using Pythagoras rule:
- Let c be the hypotenuse
- a = velocity of the ferry, and
- b = the velocity of the current, and
c² = 4² + 2²
c² = 16 + 4
c = 20
c = √20
c = 4.47 m/s
c ≈ 4.5 m/s
Therefore, the velocity of the ferry relative to the current is 4.5 m/s.
Learn more about relative velocity and Pythagoras rule at: brainly.com/question/25617868
Answer:
The average acceleration is 16.6 m/s² ⇒ 1st answer
Explanation:
A rocket achieves a lift-off velocity of 500.0 m/s from rest in
30.0 seconds
The given is:
→ The initial velocity = 0
→ The final velocity = 500 meters per seconds
→ The time is 30 seconds
Acceleration is the rate of change of velocity of the rocket
→ 
where a is the acceleration, v is the final velocity, u is the initial velocity
and t is the time
→ u = 0 , v = 500 m/s , t = 30 s
Substitute these values in the rule
→ 
m/s²
<em>The average acceleration is 16.6 m/s²</em>
