Answer:
Speed is a scalar quantity it is the rate of change in the distance travelled by an object, while velocity is a vector quantity it is the speed of an object in a particular direction.
Answer:
45 N
Explanation:
F= ma (ie force is found by multiplying the mass of the object by its accerelation)
thus, F = 15 X 3 = 45 N
Answer: 3.13 m
Explanation:
Given
mas of the ball is m=10 kg
The ball rolls down a vertical distance of 5 m
Spring constant of spring is 
Here, the potential energy of the ball converted into kinetic energy which in turn converts into elastic potential energy
![\Rightarrow mgh=\frac{1}{2}kx^2\quad [\text{x=compression in the spring}]\\\\\Rightarrow 10\times 9.8\times 5=\frac{1}{2}\cdot 100\cdot x^2\\\Rightarrow x=\sqrt{9.8}\\\Rightarrow x=3.13\ m](https://tex.z-dn.net/?f=%5CRightarrow%20mgh%3D%5Cfrac%7B1%7D%7B2%7Dkx%5E2%5Cquad%20%5B%5Ctext%7Bx%3Dcompression%20in%20the%20spring%7D%5D%5C%5C%5C%5C%5CRightarrow%2010%5Ctimes%209.8%5Ctimes%205%3D%5Cfrac%7B1%7D%7B2%7D%5Ccdot%20100%5Ccdot%20x%5E2%5C%5C%5CRightarrow%20x%3D%5Csqrt%7B9.8%7D%5C%5C%5CRightarrow%20x%3D3.13%5C%20m)
Thus, the spring compresses by 3.13 m.
Answer:
car1: a=3.1m/s^2 , car2: a=6.1m/s^2
(a) 1/2*3.1*t^2= 1/2*6.1*(t-0.9)^2
1.55t^2= 3.05(t^2-1.8t+0.81)= 3.05t^2-5.49t+2.4705
1.5t^2-5.49t+2.4705= 0
t= 3.13457 = 3.14[s] after.
(b) d= 1/2*3.1*3.13457^2= 15.23[m] approx.
(c) car1: v=at = 3.1*3.13457= 9.717m/s
car2: v=at = 6.1*(3.13457-0.9)= 13.631m/s
13.631-9.717= 3.914 = 3.91[m/s] faster than car1.
