Answer: 12) 1.07 m/s (right) 13) 4.05 m/s 14) 73 m/s 15) 10.9 m/s
Explanation:
12) Conservation of momentum. Momentum is the produce of mass and velocity.
13(2) + 15(-5) = 13(-5) + 15v
v = 1.06666... ≈ 1.07 m/s (right)
13) 18(9) + 22(0) = 18v + 22v
v = 18(9)/40 = 4.05 m/s
14) 0.65(35) + 0.08(0) = 0.65(26) + 0.08v
v = 73.125
15) This is a bit trickier. Let's ASSUME you jump off at 7 m/s relative to the truck. Doing this, we can assume that the reference frame is moving along with the truck at 10 m/s
the conservation of momentum equation becomes
600(0) + 80(0) = 600v + 80(-7)
v = 0.9333333... m/s
adding back the velocity of the reference frame means the truck is now traveling.
10.9333333... ≈ 10.9 m/s
<h2>Soccer player practices kicking the ball </h2>
The player has 15 meters per second ( m/s ) average velocity of the ball. In order to calculate, we know that the formula of calculating the velocity is velocity = displacement / time.
A player practices kicking the ball into the goal from halfway down the soccer field. Half displacement will be considered which is 45 meters and time interval is given which is 3 seconds. By putting values in the formula v = d / t ( 45 / 3 ) = 15, we get 15 m / s average velocity.
Answer:
5501 kg/m^3
Explanation:
The value of g at the Earth's surface is
where G is the gravitational constant
M is the Earth's mass
is the Earth's radius
Solving the formula for M, we find the value of the Earth's mass:
The Earth's volume is (approximating the Earth to a perfect sphere)
So, the average density of the Earth is
Answer:
4 m/s
Explanation:
M = mass of the hammer = 8.91 kg
m = mass of the metal piece = 0.411 kg
h = height gained by the metal piece = 3.88 m
Potential energy gained by the metal piece is given as
PE = mgh
PE = (0.411) (9.8) (3.88)
PE = 15.6 J
KE = Kinetic energy of the hammer
Given that :
Potential energy of metal piece = (0.219) Kinetic energy of the hammer
PE = (0.219) KE
15.6 = (0.219) KE
KE = 71.2 J
v = speed of hammer
Kinetic energy of hammer is given as
KE = (0.5) M v²
71.2 = (0.5) (8.91) v²
v = 4 m/s
Given that,
Mass of the object, m = 1 kg
It moves in a circle of radius 0.5 m with a speed of 5 m/s
To find,
The direction of the acceleration.
Solution,
Whenever an object moves in a circular path, the only force that acts on its is centripetal force which is given by the formula as follows :
The centripetal acceleration acts in the direction of force. It acts along the radius of the circular path. In this figure, the direction of the acceleration is shown at point d.
