Assume the ball was thrown at ground level, so its initial position vector is . Let denote the ball's initial speed and the angle at which the ball is thrown.
Over time, its position changes according to , where the components are determined by
where is the acceleration due to gravity. We know the ball is in the air for 4.5 seconds and that it travels a horizontal distance of 45 meters, which means
Divide the second equation by the first to eliminate , and we can solve for , expecting some solution within :
Then plugging this into either equation above will tell us the ball's initial speed:
Answer:
7.5 km/hr
Explanation:
All you have to do is divide 15 km by 2 hours and you get 7.5 km/hr.
Solution :
The given figure is a loop of a wire with a resistor.
When the switch S is closed for long time and is suddenly opened, the direction of the induced current can be find out by using the rule of right hand screw. According to the right hand screw rule, the direction of the magnetic field at the loop is in the direction that points outwards. The strength of the current rapidly decreases as it is switch off and the magnetic flux that is linked with the loop wire will also decrease.
According to the Lenz's law, the direction of the induced current must be such the decrease in the magnetic flux. It means the direction of the magnetic field must be outwards and also normal to the plane of the screen. The direction of the induced anti clockwise or from right to left in the resistance.
Answer:
Explanation:
To find the force we proceed by defining the variables we have,
The charge on one of the balls is defined under the equation,
Due to the height we need to calculate the potential energy at the height of 115m,
The kinetic energy would be given by
From the law of conservation we equate the two equations
In this way we now calculate the strength of the particle