Answer:
Velocity (magnitude) is 98.37 m/s
Explanation:
We use the vertical component of the initial velocity, which is:
Using kinematics expression of vertical velocity (in y direction) for an accelerated motion (constant acceleration, which is gravity):
Now we need to find 
as a function of 
. We use the horizontal velocity, which is always the same as follow:
We know the angle at 3 seconds:
Substitute 
in 
and then solve for
With this expression we go back to the kinematic equation and solve it for initial speed
Answer: 65000 seconds
Explanation:
Given that,
Current (I) = 2 mA
(Since 1 mA = 1 x 10^-3A
2 mA = 2 x 10^-3A)
Charge (Q) = 130 C
Time taken for a fully charged phone to die (T) = ?
Recall that the charge is the product of current and time taken.
i.e Q = I x T
130C = 2 x 10^-3A x T
T = 130C / (2 x 10^-3A)
T = 65000 seconds (time will be in seconds because seconds is the unit of time)
Thus, it will take a fully charged phone 65000 seconds to die
Answer:
Explanation:
Given that,
5J work is done by stretching a spring
e = 19cm = 0.19m
Assuming the spring is ideal, then we can apply Hooke's law
F = kx
To calculate k, we can apply the Workdone by a spring formula
W=∫F.dx
Since F=kx
W = ∫kx dx from x = 0 to x = 0.19
W = ½kx² from x = 0 to x = 0.19
W = ½k (0.19²-0²)
5 = ½k(0.0361-0)
5×2 = 0.0361k
Then, k = 10/0.0361
k = 277.008 N/m
The spring constant is 277.008N/m
Then, applying Hooke's law to find the applied force
F = kx
F = 277.008 × 0.19
F = 52.63 N
The applied force is 52.63N
Answer:Racquet force is twice of Player force
Explanation:
Given
ball arrives at a speed of 
ball returned with speed of 
average Force imparted by racquet on the ball is given by
where 
time of contact of ball with racquet
When it land on the player hand its final velocity becomes zero and time of contact is same as of racquet
From 1 and 2 we get
Hence the magnitude of Force by racquet is twice the Force by player
The right answer to this question is A. a crest that is toppling over. When a surfer rides an ocean wave on her surfboard, she is actually riding on a crest. The crest is the point on a wave with the maximum value or upward displacement within a cycle.
