A student throws a set of keys vertically upward to his fraternity brother, who is in a window 4.05 m above. The brother's outstretched hand catches the keys 1.45 s later. (Take upward as the positive direction. Indicate the direction with the sign of your answer.) (a) With what initial velocity were the keys thrown? (b) What was the velocity of the keys just before they were caught?

Q: An object undergoes acceleration when it changes    what  is the asnwer?   a) speed only   b)…

A: Answer:- (c) both speed and direction  An object undergoes acceleration when it changes both speed…

Q: A soccer ball is kicked 8m north. Then a teammate kicks it 6m east into the goal. What is the soccer…

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Q: If the speed of the lifeguard on sand is 4.00 m/s and she swims at 1.00 m/s, how much time will she…

A: AD=150 mBD=50+60=110 mFC=25 mBC=60 mEF=DC=50 mAE=150−25=125 m

Q: se the position equation s = −16t2 + v0t + s0 where s represents the height of an object (in feet),…

A: Givens = -16t2 + v0t + s0s0=0v0 = 128 feet per second

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A: Say initial velocity is u. Acceleration due to gravity on Earth is g Angle of projection is θ Range…

Q: The world long jump record is 8.95m. Treated as a projectile, what is the maximum range obtainable…

A: Given data:  Initial speed (V0) = 9.5 m/s2 Angle (θ) = 45° Required: The maximum horizontal range

Q: When a ball was allowed to fall from rest from height h, a second ball was thrown up from the ground…

A: The initial height of the first ball is given as h. The initial velocity of the first ball is given…

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Q: Which of the following statements INCORRECTLY describes the horizontal motion of a projectile? •The…

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Q: A ball is equipped with a speedometer 30 40 and launched straight upward. The speedometer reading…

A: In this solution, upward direction is taken as positive and downward direction is taken as negative.…

Q: A ball is thrown vertically up and reached a maximum height of 50 feet. With what velocity was it…

A: Given data: The maximum height reached by the ball, h=50 ft. Conventionally, the initial velocity…

Q: How do you calculate the total time a projectile is in flight given only the initial velocity and…

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Q: A circus player throws his balls vertically upwards for a distance of 1 m. How high must he throw…

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Q: Which of the following situation both the instantaneous velocity and the acceleration of a coconut,…

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Q: The velocities of commuter trains A and B are as shown. Knowing that the speed of each train is…

A: Velocity of A is 66 km/hr in negative x direction. In vector form we can write it as,

Q: To find the height of an overhead power line, you throwa ball straight upward. The ball passes the…

A: Let t1 be the time at which the ball passes the power line on the way up and t2 be the time at which…

Q: In which of the following conditions would the average velocity vector over an interval equal to the…

A: The average velocity is the ratio of displacement and time. Consider the body is moving along a…

Q: Which of the following statements are true of the time of flight for a projectile? List all that…

A: Given:  Time of flight of a projectile.

Q: While standing on a bridge 18.1 m above the ground, you drop a stone from rest. When the stone has…

A: Time taken by first stone to strike the ground -  Using kinematic equation -  Where u = Initial…

Q: Which of the following statement is/are true? (A) The acceleration in free fall at the maximum…

A:

Q: Starting at a height of 8 m, and fired upwards at 11 m/s, how much time is projectile in the air…

A: Given - Displacement of the projectile, y =- 8 m Initial velocity , u = 11 m/s  Acceleration due to…

Q: A ball was thrown plumbly upward and then returned in the same path, and its launcher picked it up 5…

A:

Q: Now, imagine an elephant and a feather under free-fall (if there is no air resistance) being dropped…

A: The velocity of freely falling body can be expressed as, v2=u2+2as=02+2ghv=2gh

Q: the ball is thrown upward straight from the top of the tower with an initial velocity 20 m/s the…

A: At maximum height the final velocity will be zero. Equation of motion having acceleration due to…

Q: A ball on the ground is kicked at an angle of 45 degrees with a velocity of 28 feet per second.  How…

A: Given- Velocity of ball (U) = 28 ft/sec, Kicked at an angle (θ) = 450

Q: From a height of 70 ft above ground, an item is flung vertically upward. The object’s starting…

A: The height of the item from the ground, h=70 ft The initial velocity of the item from the height,…

Q: A boat can travel 2.3 m/s in still water. If the boat travels across a stream whose current is 1.2…

A: Given   v1 = 2.3m/s  v2 = 1.2 m/s

Q: In which component of motion of a projectile is described as an accelerated motion? O vertical…

A: To determine,Which component of the motion of projectile is an accelerated motion.

Q: A student throws a set of keys vertically upward to her friend, who is in a window 3.20 m above. The…

A: Given data The distance travelled by the keys is: d = 3.20 m The time is taken by the key to…

Q: A ball is equipped with a speedometer and launched straight upward. The speedometer reading three…

A: Given: Speed of the ball at time t = 3 sec is u = 30 m/s So the height of the ball at time t = 3sec…

Q: When the direction of a car's velocity is opposite of the direction of its acceleration, then it is…

A: When a car is moving with a velocity in a particular direction.

Q: Object A was dropped from a crane and object B was thrown upward from the same position.When they…

A:

Q: A student throws a set of.keys vertically upward to her friend, who is in a window 4.00 m above. The…

A:

Q: A weather balloon is released and rises vertically such that its distance s(1) above the ground…

A: Since you have asked multiple questions, we will solve the first question for you. If you want a…

Q: In a local bar, a customer slides an empty beer mug down the slippery counter for a refill. The…

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Q: 20 The velocity of a projectile equals its initial velocity added to : la constant horizontal…

A: When a projectile is thrown up, it's velocity become zero at the highest point of the trajectory .…

Q: Which expression correctly gives the total time the projectile spends in the air? t = _______ a)…

A:

Q: Is the acceleration of an object equal to zero when a projectile reaches the top of its trajectory?

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Q: Use a graphing utility to obtain the path of a projectile launched from the ground (h = 0) at the…

A: An object thrown obliquely near the Earth's surface, moves in a curved path. The object is called as…

Q: A building is under construction, and a construction worker is standing on top of a 130 m high…

A: Given : Height from which hammer drops (h) = 130 m Initial speed (u) =0 Acceleration due to gravity…

Q: A football is thrown horizontally with an initial velocity of116.6 m>s2xn . Ignoring air…

A:

Q: A volleyball is thrown with an initial velocity of 30 m/s at an angle of 40 degrees above the…

A:

Q: What is the acceleration of a projectile fired vertically downwards? Is it positive or negative?

A: To discuss whether the acceleration of a projectile fired vertically downwards is  positive or…

Q: The player threw the tool disc at a speed of (21,5 m / Sc) and the height of the starting point from…

A: When any object is projected in air with an angleθ from the horizontal surface at initial velocity…

Q: A tennis ball is thrown so that its initial vertical and horizontal components of velocity at 40 m/s…

A: Given that the initial vertical and horizontal component of velocity.Then We have to determine the…

Relative Velocity

It is a measurement of an object with regards to the other object which is moving or stable or stationary. For example, if we are traveling in a bus and the bus is moving at speed of 50km/hr, then our speed is according to the nearby passenger on the bus is zero. According to them, we are not moving. But if one person standing on the ground or road observes us from outside of the bus, according to him we are moving at a speed of 50km/hr and the bus is also moving at a speed of 50km/hr. Now, the motion is recognized by the observer, it depends on a frame of reference or observer. This is motion called relative motion.