Answer:
5 .07 s .
Explanation:
The child will move on a circle of radius r
r = 1.5 m
Let the velocity of rotation = v
radial acceleration = v² / r
v² / r = 2.3
v² = 2.3 r = 2.3 x 1.5
= 3.45
v = 1.857 m /s
Time of revolution = 2π r / v
= 2 x 3.14 x 1.5 / 1.857
= 5 .07 s .
During either one, the sun, moon, and Earth are lined up in the same straight line. The difference is whether the moon or the Earth is the one in the "middle".
Answer:
Explanation:
If a car is moving to the left with constant velocity, one can conclude that
there must be no forces applied to the car . The net force applied to the car is zero.
Since there is no acceleration ,no net force is applied , hence no force acts on the car.
Answer:
Explanation:
It is given that,
Angular speed of the football spiral, 
Radius of a pro football, r = 8.5 cm = 0.085 m
The velocity is given by :
v = 3.68 m/s
The centripetal acceleration is given by :
So, the centripetal acceleration of the laces on the football is 
. Hence, this is the required solution.
Answer:
The correct answer is - 63.61 miles/hour.
Explanation:
Meter and miles both are the measuring units of distance and speed units are meter per second and miles per hour. The numerical relation between these two units are as follows:
1 meter per second = 2.24 miles per hour
The car travels 28.4 m/s so in miles per hour it would be:
So, 28.4 meters per second = 28.4 * 2.24 miles per hour
28.4 meters per second = 63.61 miles per hour.
Thus, the correct answer is - 63.61 miles per hour.
