Answer:
Explanation:
The acceleration of gravity is 9.8m/s^2.
So to calculate the time it will take to make the ball stop(which btw means the ball now reach its greatest height), use the formula V1=V0+at. V1 is the final velocity(which is 0), V0 is the starting velocity(which is 30m/s), and the a(cceleration) is 9.8m/s^2.
(You can ignore the fact "at" is -30 instead 30, it's because the directions two velocity travel are opposite. )
We can now know the time it takes to make the ball stop just by the gravitational force is about 3 sec.
Use another formula S=1/2at^2, to find out the S(height) is 1/2*9.8*3^2=44.1, which is approximately D.45m .
Answer:
10259.6 m
Explanation:
We are given that
Radius of small wheel,r=0.17 m
Radius of large wheel,r'=0.92 m
Initial velocity,u=0
Time,t=2.7 minutes=162 s
1 min=60 s
Velocity,v=10m/s
Time,t'=13.7 minutes=822 s
Time,t''=4.1 minutes=246 s

Substitute the values



Substitute the values




Total distance traveled by rider=s+s'+s''=809.6+8220+1230=10259.6 m
Answer:
1.05 J.
Explanation:
Kinetic Energy: This is the energy possessed by a body due to its motion. The S.I unit of kinetic energy is Joules (J). The formula of kinetic energy is given as
Ek = 1/2mv²................. Equation 1
Where Ek = kinetic energy, m = mass of the uniform rod, v = liner velocity of the rod.
But,
v = αr .......................... Equation 2
Where α = angular velocity of the rod, r = radius of the circle.
Given: α = 3.6 red/s, r = 120/2 = 60 cm = 0.6 m.
Substitute into equation 2
v = 3.6(0.6)
v = 2.16 m/s.
Also given: m = 450 g = 0.45 kg.
Substitute into equation 1
Ek = 1/2(0.45)(2.16²)
Ek = 1.05 J.
Answer:
0.625 c
Explanation:
Relative speed of a body may be defined as the speed of one body with respect to some other or the speed of one body in comparison to the speed of second body.
In the context,
The relative speed of body 2 with respect to body 1 can be expressed as :

Speed of rocket 1 with respect to rocket 2 :



Therefore, the speed of rocket 1 according to an observer on rocket 2 is 0.625 c
Answer: 117.6N
Explanation:
By the second Newton's law, we know that:
F = m*a
F = force
m = mass
a = acceleration
We know that in the surface of the Earth, the gravitational acceleration is g = 9.8m/s^2.
Then we just can input that acceleration in the above equation, and also replace m by 12kg, and find that the force due the gravity is:
F = 12kg*9.8m/s^2 = 117.6N