Pls sir, kindly send the solution to my email. thanks.

1)A boat propelled so as to travelled with a speed of 0.50m/s in still water, moves directly ( in straight line ) across a river that is 60m wides. The river flow with a speed of 0.30m/s. How long in seconds does it take the boat across the river?

2)A rope suspended from a ceiling supports an object of weight at its opposite end. Another rope tied to the first at the middle is pulled horizontally with a force of 30N. The junction P of the rope is in equilibrium. Calculate the weight and the Tension?

3)A 150kg ladder leans against a smoothwall, making an angles of 30degrees with the floor. The center of gravity of the ladder is one-third the way up from bottom. How large a horizontal force must the floor provide if the ladder is not to slip?

4) A body hangs from springs balance supported from roof of an elevator. if the elevator has an upward acceleration of 3m/s square and the balance reads50N, what is the true weight of the body?

I'm sorry, but as an AI text-based bot, I cannot directly send solutions to your email. However, I can provide you with step-by-step explanations and solutions to the problems you have listed here. Let's go through each problem:

1) To find out how long it takes for the boat to cross the river, we need to determine the time it takes for the boat to cover the horizontal distance. We can use the formula: time = distance / speed.

In this case, the distance is the width of the river, which is 60m. The boat's speed is the speed it travels in still water, which is 0.50m/s. However, since the river is flowing, the boat's velocity relative to the ground will be the vector sum of its velocity in still water and the river's velocity.

To calculate the boat's velocity relative to the ground, we subtract the velocity of the river from the velocity of the boat. Therefore, the boat's velocity relative to the ground is: 0.50m/s - 0.30m/s = 0.20m/s.

Now we can calculate the time it takes for the boat to cross the river using the formula: time = distance / speed. Plugging in the values, we get: time = 60m / 0.20m/s = 300 seconds.

So, it will take the boat 300 seconds to cross the river.

2) In this problem, we have an object hanging from a rope suspended from the ceiling. Another rope is tied to the first rope at the middle and pulled horizontally with a force of 30N. The junction P of the rope is in equilibrium.

Since the junction P is in equilibrium, the forces acting on it must balance out. The vertical force acting on the junction is the weight of the object, and the horizontal force is the pull on the rope.

To calculate the weight of the object, we equate the vertical forces: weight = tension in the rope.

To calculate the tension in the rope, we equate the horizontal forces: tension = 30N.

So, the weight of the object is 30N, and the tension in the rope is also 30N.

3) In this problem, we have a ladder leaning against a smooth wall. The ladder weighs 150kg and makes an angle of 30 degrees with the floor. The center of gravity of the ladder is one-third the way up from the bottom.

To calculate the horizontal force that the floor needs to provide to prevent the ladder from slipping, we need to consider the forces acting on the ladder. There are two forces involved: the weight of the ladder acting downwards and the normal force exerted by the floor acting upwards.

The weight of the ladder can be split into two components: the vertical component and the horizontal component. The vertical component is given by weight * cos(angle), and the horizontal component is given by weight * sin(angle).

Since the ladder is in equilibrium, the sum of the horizontal forces should be zero. Therefore, the horizontal component of the weight must be balanced by the horizontal force provided by the floor.

Setting up the equation: horizontal force = weight * sin(angle).

Plugging in the values, we get: horizontal force = 150kg * 9.8m/s^2 * sin(30 degrees) = 735N.

So, the floor needs to provide a horizontal force of 735N to prevent the ladder from slipping.

4) In this problem, a body hangs from a spring balance supported from the roof of an elevator. The elevator has an upward acceleration of 3m/s^2, and the balance reads 50N.

The true weight of the body can be calculated by using Newton's second law: force = mass * acceleration.

The force acting on the body is the sum of the tension in the balance and the weight of the body. In this case, the tension in the balance is given as 50N.

Therefore, force = tension + weight.

To find the weight, we rearrange the equation: weight = force - tension.

Plugging in the values, we get: weight = (mass * acceleration) - tension = (mass * 3m/s^2) - 50N.

Since the mass is unknown, we cannot calculate the exact value of the weight without additional information.

I hope these explanations help you understand how to approach these types of problems. If you have any further questions, feel free to ask.