Answer:
4 m/s in negative acceleration
Explanation:
Acceleration = V- U/t
Where V is the final velocity
U is the initial velocity and t is the time given.
U = 65 m/s
V= 25 m/s
T= 10 seconds
Acceleration= (25m/s - 65m/s)÷10secs
= - 40/10
= -4m/s^2
Hence, it has a negative acceleration.
Answer:
m = 9795.9 kg
Explanation:
v = 35 m/s
KE = 6,000,000 J
Plug those values into the following equation:

6,000,000 J = (1/2)(35^2)m
---> m = 9795.9 kg
Answer:
electromagnetic waves
Explanation:
"wave" is a common term for a number different ways in which energy is transferred
Answer:
a) 4.45 m/s
b) 0.9 seconds
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration due to gravity = 9.81 m/s²

a) The vertical speed when the player leaves the ground is 4.45 m/s

Time taken to reach the maximum height is 0.45 seconds

Time taken to reach the ground from the maximum height is 0.45 seconds
b) Time the player stayed in the air is 0.45+0.45 = 0.9 seconds
Newton's second law states that the resultant of the forces applied to an object is equal to the product between the object's mass and its acceleration:

where in our problem, m is the mass the (child+cart) and a is the acceleration of the system.
We are only concerned about what it happens on the horizontal axis, so there are two forces acting on the cart+child system: the force F of the man pushing it, and the frictional force

acting in the opposite direction. So Newton's second law can be rewritten as

or

since the frictional force is 15 N and we want to achieve an acceleration of

, we can substitute these values to find what is the force the man needs: