Answer:
2.47 s
Explanation:
Convert the final velocity to m/s.
We have the acceleration of the gazelle, 4.5 m/s².
We can assume the gazelle starts at an initial velocity of 0 m/s in order to determine how much time it requires to reach a final velocity of 11.1111 m/s.
We want to find the time t.
Find the constant acceleration equation that contains all four of these variables.
Substitute the known values into the equation.
- 11.1111 = 0 + (4.5)t
- 11.1111 = 4.5t
- t = 2.469133333
The Thompson's gazelle requires a time of 2.47 s to reach a speed of 40 km/h (11.1111 m/s).
Answer:
1.63 m/s
Explanation:
a = acceleration of the ball
d = stopping distance = 23.5 - 5.10 = 18.4 ft = 5.61 m
v₀ = initial velocity of the car = 1.45 m/s
v = final velocity of the car = 0 m/s
Using the equation
v² = v₀² + 2 a d
0² = 1.45² + 2 a (5.61)
a = - 0.187 m/s²
To win the tournament :
a = acceleration of the ball = - 0.187 m/s²
d = stopping distance = 23.5 ft = 7.1 m
v₀ = initial velocity of the car = ?
v = final velocity of the car = 0 m/s
Using the equation
v² = v₀² + 2 a d
0² = v₀² + 2 (- 0.187) (7.1)
v₀ = 1.63 m/s
Answer:
R' = R/4
Explanation:
The resistance of a metal rod is R. It is given by the relation as follows :
Where
l is the length and A is the area of cross-section
If both its length and its diameter are quadrupled, it means,
l' = 4l
and d'= 4d
It means,
Let new resistance be R'. So,
So, the correct option is (B) "R/4".