Answer:
C. 30.6m
Explanation:
To find the height of the tower, we are to use Newtons law of motion to solve this problem. Since the penny is falling from the top of the tower, it is acted by the acceleration due to gravity. The formula to be used is:
Where H is the height of the tower, t is the time taken to hit the ground, u is the initial velocity and g is the acceleration due to gravity.
Given that, t = 2.5 s, g =9.8 m/s², u = 0 m/s (at the top of tower)
Answer:
0.76 s
Explanation:
We are given that
Length of rod,L=20 cm=
1 m=100 cm
Mass of rod,M=190 g=
Mass of ball,m=19 g=
Using 1 kg=1000g
We have to find the period if the rod and clay swing as a pendulum.
Moment of inertia of rod-clay=Moment of inertia of rod+moment of inertia of clay
Substitute the values then we get
Now, the center of mass of the combination of the rod and clay is given by
Substitute =Distance between pivot and the center of the rod
The distance between rod and clay
Using the formula
m
Time period of the oscillation of the system of the rod and the clay is given by
g=
Using the formula
Time period=
Time-period=0.76 s
Hence, the period =0.76 s