Answer:
40 m/s
Explanation:
given,
height of the fall, h = 82 m
time taken to fall, t = 1.3 s
rock velocity, v = ?
acceleration due to gravity, g = 9.8 m/s²
rock is released initial velocity, u = 0 m/s
using equation of motion
v² = u² + 2 a s
v² = 0 + 2 x 9.8 x 82
v² = 1607.2
v = 40 m/s
hence, rock's velocity is equal to 40 m/s
Answer:
The wave speed is calculated below:
Explanation:
Given,
number of waves passed per minute = 8
time period = 1 minute = 60 s
distance between successive wave crests = 20 m
waves passing interval per second = 
Now,
wave speed = 20 m ×
= 
m/s
= 2.67 m/s
Hence the wave speed is 2.67 m/s.
Answer:
25 mm = 0 deg C
200 mm = 100 deg C
200 - 25 = 175 = change in thread per 100 deg C
95 - 25 = 70 mm - change in thread from 0 deg C
70 / 175 * 100 = 40 deg C final temperature at 95 mm
Answer:
Mass of the box is 25kg
Explanation:
From Newton's second law of motion
Force= mass. acceleration
With the symbol
F=m.a
m=F/a m=(50N)/(2m/s²)
m=25kg
Answer:
D) 8
Explanation:
Due to the octet rule the most stable atoms will have 8 valence electrons.
