The ball's horizontal component of velocity (ie it's horizontal speed) is 20 cos 40degrees. Without knowing the distance of the ball to the wall it's difficult to go further ...
Answer:
D. Newton's second law
Explanation:
Newton's second law of motion states that force of an object is a product of its mass and its acceleration.
Mathematically, F= ma where m is mass and a is acceleration
So from the statement above : The acceleration of an object is proportional to the force applied to it and inversely proportional to its mass , it can be seen from the formula variation as;
F= ma -----making a the subject of the formula
a= F/ m
a= 1/m * F --------- a is inversely related to m as you can see from 1/m but directly related to F hence;
Increase in mass with the same force applied causes the body to accelerate slower where as when force increases, the body accelerates faster.
Explanation:
The Coulomb's law states that the magnitude of each of the electric forces between two point-at-rest charges is directly proportional to the product of the magnitude of both charges and inversely proportional to the square of the distance that separates them:

In this case we have an electron (-e) and a proton (e), so:

In this case, the electric force is negative, therefore, the force is repulsive and its magnitude is:

Answer:
70.6 mph
Explanation:
Car A mass= 1515 lb
Car B mass=1125 lb
Speed of car B is 46 miles/h
Distance before locking, d=19.5 ft
Coefficient of kinetic friction is 0.75
Initial momentum of car B=mv where m is mass and v is velocity in ft/s
46 mph*1.46667=67.4666668 ft/s
Initial momentum of car A is given by
where
is velocity of A
Taking East as positive and west as negative then the sum of initial momentum is
The common velocity is represented as
hence after collision, the final momentum is
From the law of conservation of linear momentum, sum of initial and final momentum equals each other hence
The acceleration of two cars
From kinematic equation
hence
Substituting the value of
in equation
<h2>
Option 1 is the correct answer.</h2>
Explanation:
Power of heater, P = 1790 W
Time used, t = 24 hours = 24 x 60 x 60 = 24 x 3600 s
We have the equation

We need to find energy,
Substituting

Energy = 1790 x 24 x 3600 J
Option 1 is the correct answer.