Answer:
The speed with which the pebble strikes the ground is 30.4m/s
Explanation:
Initial velocity (u) = 17.5m/s, height (h) = 31.5m, acceleration due to gravity (g) = 9.8m/s^2
V^2 = u^2 + 2gh = 17.5^2 + 2×9.8×31.5 = 306.25 + 617.4 = 923.65
V^2 = 923.65
V = √923.65 = 30.4m/s
Answer:
Friction force always acts tangent to the surface at points of contact. Friction force acts opposite to the direction of motion. There are 2 types of friction: Static friction: If the two surfaces in contact do not move relative to each other, one has static friction.
Answer:
222.2N/m
Explanation:
Given parameters:
Elastic potential energy = 4000J
Extension = 6m
Unknown:
Spring coefficient = ?
Solution:
The elastic potential energy is the energy stored within a string.
It is expressed as;
EPE =
k e²
k is the spring constant
e is the extension
4000 =
x k x 6²
8000 = 36k
k = 222.2N/m
This is an <em>inelastic </em>collision. The equation for an inelastic collision is: 
(110)(6) + (150)(-4) = (110 + 150)(vf)
660 - 600 = 260vf
60 = 260vf
vf = 0.2308 m/s
They will travel in the positive direction, right, and their combined velocity will be 0.2308 m/s.
Hope this helps!! :)