Answer:
(a) 
(b) 142
(c) 
(d) 96.8 mph
(e) 0.426 s
(f) 0.061 rad
Explanation:
Velocity is a time-derivative of position.
(a) 

(b) Since
is independent of
, it follows it was constant throughout. Hence, at any point or time, the horizontal velocity is 142.
(c) 

(d) When it passes the home plate, the ball has travelled 60.5 ft (from the question). This is horizontal, so it is equivalent to
.

.
In this time, the vertical velocity,
is

The speed of the ball at thus point is
ft/s
To convert this to mph, we multiply the factor 3600/5280

(e) The time has been determined from (d) above.

(f) This angle is given by

(Note here we are considering the acute angle so we ignore the negative sign)
In radians, this is

Answer:
1.) Magnitude = 5596 N
2.) Direction = 60 degrees
Explanation: You are given that the breakdown vehicle A is exerting a force of 4000 N at angle 45 degree to the vertical and breakdown vehicle B is exerting a force of 2000 N
Let us resolve the two forces into X and Y component
Sum of the forces in the X - component will be 4000 × cos 45 = 2828.43 N
Sum of the forces in the Y - component will be 2000 + ( 4000 × sin 45 )
= 2000 + 2828.43
= 4828.43 N
The resultant force R will be
R = sqrt ( X^2 + Y^2 )
Substitutes the forces at X component and Y component into the formula
R = sqrt ( 2828.43^2 + 4828.43^2 )
R = sqrt ( 31313752.53 )
R = 5595.87 N
The direction will be
Tan Ø = Y/X
Substitute Y and X into the formula
Tan Ø = 4828.43 / 2828.43
Tan Ø = 1.707106
Ø = tan^-1( 1.707106 )
Ø = 59.64 degree
Therefore, approximately, the magnitude and direction of the resultant force on the truck are 5596 N and 60 degree respectively.
Inertia IS always present. Inertia is NOT the force that causes objects to continue moving in circles, that is centripetal force. Centripetal force is NOT always present. Centripetal force DOES pull objects toward the center of a circle. <span> Inertia and centripetal force DOES cause circular motion. Thank you and eat sand fren ;)</span>
Answer:
F = 39.2 N (hand force) and N = 68.6 N (shoulder force)
Explanation:
In this exercise we must use the rotational and translational equilibrium conditions, we have several forces: the weight (W) of the pole applied at its geometric center, the load (w1) at one end, the shoulder support (N) 60 cm from the load and hand force (F) at the other end of the pole
Let's set the reference system at the fit point of the shoulder
∑ τ = 0
We will assume that the counterclockwise turns are positive
w₁ 0.60 + W 0.1 + F₁ 0 - F 0.4 = 0
all distances are measured from the support of the man (x₀ = 0.60 m)
F = (w₁ 0.60 + W 0.1) / 0.4
F = (m₁ 0.6 + m 0.1) g / 0.4
let's calculate
F = (2.6 0.6 + 0.4 0.1) 9.8 / 0.4
F = 39.2 N
this is the force that the hand must exert to keep the system in balance
We apply the translational equilibrium condition
-w₁ -W + N - F = 0
N = w₁ + W + F
N = (m₁ + m) g + F
let's calculate
N = (2.6 + 0.4) 9.8 + 39.2
N = 68.6 N
Answer:
0.775
Explanation:
The weight of an object on a planet is equal to the gravitational force exerted by the planet on the object:

where
G is the gravitational constant
M is the mass of the planet
m is the mass of the object
R is the radius of the planet
For planet A, the weight of the object is

For planet B,

We also know that the weight of the object on the two planets is the same, so

So we can write

We also know that the mass of planet A is only sixty percent that of planet B, so

Substituting,

Now we can elimanate G, MB and m from the equation, and we get

So the ratio between the radii of the two planets is
