Answer:
7.5 m/s²
Explanation:
Given:
v₀ = 0 m/s
v = 30 m/s
t = 4 s
Find: a
v = at + v₀
(30 m/s) = a (4 s) + (0 m/s)
a = 7.5 m/s²
Answer:


Explanation:
m = Mass of each the cars = 
= Initial velocity of first car = 3.46 m/s
= Initial velocity of the other two cars = 1.4 m/s
v = Velocity of combined mass
As the momentum is conserved in the system we have

Speed of the three coupled cars after the collision is
.
As energy in the system is conserved we have

The kinetic energy lost during the collision is
.
Answer:
F = -307.4 N
Explanation:
It is given that,
Mass of the baseball, m = 0.145 kg
Initial speed of the baseball, u = 60 m/s
Final speed of the baseball, 
Time of contact, 
(a) It is assumed to find the horizontal component of average force. It is given by :
F = -307.4 N
So, the horizontal component of average force is 307.4 N. Hence, this is the required solution.
The second law states that the total entropy can never decrese over time for an isolated system
The Image distance and Magnification of The Image will be 30 cm and 3.
<h3>What is focal length?</h3>
The focal length of the lens, which is often expressed in millimeters, is the distance between the lens and the image sensor when the subject is in focus.
Given data;
Focal length,f=?
Image distance,v=?
Object distance,u= 10 cm
Magnification,m= 2.85
The focal length is half of the radius;
f=R/2
f=30 Cm/2
f= 15 Cm
The mirror equation is found as;

The magnification of the lens is found as;

Hence, the image distance and magnification of The image will be 30 cm and 3.
To learn more about the focal length refer;
brainly.com/question/16188698
#SPJ1